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= November 10 =


== make nanorobot ==


= December 10 =
I would like to make nanorobot but i don't know what I should study. Is there a specific field of study for that?
] 04:47, 10 November 2006 (UTC)Renaud Miclette Lamarche


== Proton decay and cosmic expansion ==
::What you need to study is nanotechnology. It's an emerging field but more and more institutions are offering it in thier syllabus. What you want under your belt is physics and chemistry, and mathematics won't hurt either. ] 05:19, 10 November 2006 (UTC)


A friend's physicist father opined that the phantom energy causing more and more rapid cosmic expansion will never be as strong as the attraction of the ], so protons will not be ripped apart in the ]. Be that as it may, if the phantom energy is counter to the strong force, however weakly, wouldn't protons, consisting of quarks held together by the strong force, have an increased rate of decay in the far future? I have heard that the theories that protons do undergo decay at all have not yet been supported by experiments, though. ] (]) 13:41, 10 December 2024 (UTC)
:::] would be a good field of study to prepare for a career in building nanorobots. You might find interesting the Misplaced Pages articles on ] , ] , ] , ] , and ]. ] 06:07, 10 November 2006 (UTC)
:We have to suppose quite a few things to get to the question: suppose there is some form of ], suppose there is ], and suppose that the phantom energy reaches some plateau before getting to an energy scale high enough to create a ]. Would protons then decay at a faster rate? I don't think that's necessarily the case. Proton decay is not the same kind of process as making a quark-gluon plasma. I believe the answer depends on what kinds of operators lead to the hypothetical proton decay. --] (]) 22:49, 10 December 2024 (UTC)
::Thanks, nice clarification of the issues. You've thought through the issues more clearly and knowledgeably than I did. That's a valuable answer. But having said that, is there more information available about current speculations and theoretical work by physicists concerning proton decay interacts with cosmic expansion? I can't be the only one wondering about it and many of the people wondering about it would be physicists.] (]) 07:30, 13 December 2024 (UTC)
:::The nearest paper I came across is , but there "proton decay" actually means p<sup>+</sup> → n + e<sup>+</sup> + ν and not p<sup>+</sup> → e<sup>+</sup> + 2γ. --] (]) 20:22, 13 December 2024 (UTC)


== Language == = December 13 =


== What is the most iconic tornado photo ==
#.If someone sas that a particular language is harsh or ugly,then that's an expresstion of his or her taste.Exlain why please.
{{hat|Request for opinions}}
#.Give three(3)reasons to explain why English is currentlythe language of science.
What photo of a tornado would you say is the most iconic? I'm researching the history of tornado photography for an eventual article on it and I've seen several specific tornadoes pop up over and over again, particularly the ] and the "dead man walking" shot of the ]. Which would be considered more iconic? ] | ] | ] 17:21, 13 December 2024 (UTC)
#.Started as the variety used in South East English,Standard English is now understood and used worldwide.can you explain what is meant by Standard English?
#.Why is English used widely in India?


:At the top of this page is a bullet point stating "We don't answer requests for opinions, predictions or debate": this reads to me like a request for subjective opinions. Perhaps you would like to consider what quantifiable and referenceable metric would answer what you want to know?
Thank you very much!Please be quick!
:Presumably you also want only real tornadoes considered? Otherwise some might nominate the the twister from ], or from more recent tornado-related movies – ], anyone? :-). {The poster formerly known as 87.81.230.195} ] (]) 18:07, 13 December 2024 (UTC)
:"Swegle Studios" has a couple of YouTube videos dedicated to the backstories of famous tornado photos and video; you might find them useful in your research. , . ] (]) 18:40, 13 December 2024 (UTC)


:I googled "most iconic tornado photo" and a bunch of different possibilities popped up. I don't see how you could say that any given photo is the "most iconic". ←] <sup>'']''</sup> ]→ 18:57, 13 December 2024 (UTC)
:Please refer to the top of this page where it says to '''Do your own homework'''. We really can't stress that enough. Although, we can point you in the right direction. For instance, the article on the ] might have some answers for you. As well as articles linked off of that. ]|] 07:49, 10 November 2006 (UTC)
{{hab}}


This really doesn't seem to be a homework question, just from the question that's being asked. That being said:
:1. Maybe the ] article has something related to harshness of a language? A quick perusal of related topics brought up ] and ] as things related to the spoken "quality" of a language, though beauty is of course in the eye of the beholder.
:2. Well, one or two centuries ago the primary "scientific" language was ] and some ]. After that, the English-speaking countries sort of started to dominate scientific discourse, which led to the the adoption of English.
:3. See ] and ] (both of which are linked in the ] article).
:4. This is an extension of #2 - English is also one of the primary languages used in international business and diplomacy (another being French), so its presence in India is probably directly related to that. See also ] for a more general discussion.
:16:39, 10 November 2006 (UTC)


= December 15 =
:: If it weren't homework, if probably wouldn't say "Give three(3)reasons to explain...". ] 03:48, 11 November 2006 (UTC)


== help to identify ] ==
== Just because I'm paranoid... ==


] in New South Wales Australia]] Did I get species right? Thanks. ] (], ]) 06:56, 15 December 2024 (UTC)
Yes, I do suffer from paranoia. No this doesn't mean that someone is not out to get me. I just need someone to put me at rest really as this is nagging at the back of my mind. Would it be possible for someone to 'bug' my home, then monitor me remotely from 100 miles away? I invited someone I know online to stay with me for a couple of days last month and ever since, I have noticed things in our online communications that don't seem 'quite right' - comments suggesting that he knows things that he could only know if he were watching me. Like I say, maybe it's just me being paranoid and seeing things that aren't there. I've read the ] article and from that, it doesn't *seem* possible (he's had access to two rooms of my house, neither of which contains my computer, so it's not my machine sending out, so it would have to be a small hidden camera or a microphone - he's not had access to my house since to retrieve anything). Anyone able to help, or point me in the right direction to info that can? Thanks. Posting anon because I feel a bit embarassed asking this.
:What kind of things are you noticing? What has he been saying? Maybe we could help you think of a more reasonable explanation for his comments. ]|] 07:47, 10 November 2006 (UTC)
::One of the things he said was a reference to me being quite ill at the moment. I've never told him that I've been ill. That's what tripped me off (I do have these episodes) - thanks, but finding reasonable explanations doesn't really help me. If I could be sure of the technical side, I'd know what to be looking for. --] 07:53, 10 November 2006 (UTC)


:related: https://species.wikimedia.org/Wikispecies:Village_Pump#help_to_identify_species ] (], ]) 06:57, 15 December 2024 (UTC)
:Unless he uses equipment already in your house (such as the telephone) a bug would need to transmit. A larger range would require a bigger bug or some relay station to amplify the signal. Any transmitter requires power and unless it uses some power source already in your house, the batteries will run out after a wile. Note that this answer is not based on any knowledge of actual existing equipment, just common sense. ] 10:25, 10 November 2006 (UTC)


:FWIW, I can't detect any visible differences between the plant in this photo and the ones illustrated in the ] and the ] articles. However, the latter makes it clear that ''Polygala'' is a large genus, and is cultivated, with hybrids, so it's possible that this one could be a close relative that differs in ways not visible here, such as in the bark or roots. That may or may not matter for your purposes. {The poster formerly known as 87.81.230.195} ] (]) 10:11, 15 December 2024 (UTC)
::Call a good detective agency and ask if they have detection equipment to check your appartment. Or you can set up a fake conversation with a friend where you slag off the spy and see if there is any change in his character next time you chat. ] 10:40, 10 November 2006 (UTC)


== How to address changes to taxonomy ==
Have you tried using a metal detector? Not really claiming to be an expert in this, but common sense sort of tells me that bugging a house electronically will require things of metal. Also, when this friend was staying at your place...how often were you in contact with him/her? As in, were you almost always around him/her? Or did you sort of just leave the person in your home? If you were with him/her the whole time, except when they were sleeping, then you can probably rule out anything elaborate.


Hi all,
Otherwise, yes...keep a good record of all communications you have with him (so emails, IM logs). If you find any hard evidence of being spied on, contact the police or some expert first, instead of confronting the person.
I am a biology student brand new to wiki editing who is interested in cleaning up small articles/stubs for less known taxa. One that I've encountered is a mushroom that occurs in the pacific northwest ('']''). The article mentions that this fungus is occasionally mistaken for another fungus, '']''. <br>


However, the issue I've run into is that ''F. pinicola'' used to be considered a single species found around the world, but relatively recently was split into a few different species. The original name was given to the one that occurs in Europe, and the one in the pacific northwest (and thus could be mistaken for ''F. ochracea'') was given the name '']''.
Alternatively, exactly where did they stay in your home? It may not be that they're spying on you, but simply that the person snooped around your place during their stay. Do you keep a journal or diary or anything that they could have found? If you live with other people, the perhaps that person talked to them, and just found out some stuff about you which you haven't personally revealed. --] 11:07, 10 November 2006 (UTC)
<br>
The wiki page says <blockquote><p>Historically, this fungus has been misidentified as ''F. pinicola.'' When both species are immature, they can look very similar, but can be distinguished by lighting a match next to the surface of the fungus. ''F. pinicola'' will boil and melt in heat, while F. ochracea will not.</p></blockquote>
<br>Since the source says ''pinicola'' (as likely do most/all other sources of this info given the change was so recent), and since technically it's true that they used to be mistaken for it... what would be the most appropriate way to modernize that section?
<br>


<B>My questions are</b>:
: The longer you think about ther more ways you will imagine how somebody could spy on you, and the you will have to convince yourself for all this possibilities that they are actually not plausible or practible. Now, I feel the urge to apply to your common sense and ask yourself: why should he spy on you? But I imagine that this is harder than it sounds as you are actually suffering from an illness clouding your common-sense reasoning. I hope you have someone to help you through this, a therapist, doctor or at least some good friends that you still trust. However, one thing needs to be pointed out: You say that fact that he knew you are ill tipped you off. Make yourself aware how much "invisible" information the human voice carries. If a friend of mine whom I know well phones me I might be able to guess whether he is well or ill just from the way how he says "hello", before he even went on talking. There is no spying in this -- our brains analyse these hidden clues automatically and subconciously all the time. ] 11:54, 10 November 2006 (UTC)
Should I replace ''F. pinicola'' with ''F. mounceae''? Or is that wrong because the source doesn't refer to it by that name? Would it be better to write something like (now known as/considered ''F. mounceae'') next to the first mention of the species? Or is that a poor choice because it implies all the members of ''F. pinicola'' were renamed ''F. mounceae''?
<br>


Any advice on how to go about updating this section is incredibly appreciated
He could have a small battery-powered bug that sends a weak signal just outside the home. Then, outside, he could have a powerful rebroadcast station that's either plugged into an outside outlet or has powerful batteries. Another option would use the phone. The bug could be in the phone, and could be programmed to record everything in the room, then call him at 3 AM and upload the recording to his computer. Also, I think it's a bad idea to allow people you meet on the Internet to stay at your home normally. But, if you're the paranoid type, it's especially bad, as it will lead to this type of problem. ] 16:51, 10 November 2006 (UTC)
<br>
] (]) 10:21, 15 December 2024 (UTC)
:::First, take these sorts of questions to the relevant Wikiproject, in this case ]. I am not as familiar with the consensus at ], but it seems like they defer to '']'' and ] to decide. Those sources presently seem to consider '']'' a good species. Also, be careful about "replacing", there are rules to ensure the continuity of the article history. By the way, there is a hilarious but unencyclopedic/copyvio recipe appended to the '']'' article. <span style="font-family: Cambria;"> ] (])</span> 11:09, 15 December 2024 (UTC)
::::Thanks for the tips, I didn't know about projects so I'll go read up on that. And thanks for the warnings about replacing things. I've been reading a lot of help pages, but I'm still in the process of learning the all conventions and what mechanics break if you do things the wrong way.
::::I actually saw the recipe ages ago before I made my account and completely forgot about it... it was one of many things that prompted me to get into wiki editing. ] (]) 23:12, 15 December 2024 (UTC)


== Does stopping masturbation lead to sperm DNA damage? ==
: Was you paranoid alredy from before this someone stay with you? Is it possible he is enamored of you?
: ] 17:09, 10 November 2006 (UTC)


I'm looking for information on the potential link between the frequency of ejaculation (specifically through masturbation) and sperm DNA damage. I've come across some conflicting information and would appreciate it if someone could point me towards reliable scientific studies or reviews that address this topic.
:Yes, he absolutely could. Both via conventional monitoring technology (hardware), and thru software. Check out ] 17:17, 10 November 2006 (UTC)


Specifically, I'm interested in whether prolonged periods of abstinence from ejaculation might have any negative effects on sperm DNA integrity. Any insights or links to relevant research would be greatly appreciated. ] (]) 17:08, 15 December 2024 (UTC)
== Supercharger ==
:Only males may abstain from sperm-releasing ] that serves to flush the genital tract of old sperm that in any case will eventually dissipate. No causal relationship between masturbation and any form of mental or physical disorder has been found but abstinence may be thought or taught]]] to increase the chance of wanted conception during subsequent intercourse. ] (]) 00:51, 16 December 2024 (UTC)
::There's many rumors about that topic. One is that not ejaculating frequently increases the risk of developing ]. <span style="font-family: Cambria;"> ] (])</span> 01:02, 16 December 2024 (UTC)
:Nothing really conclusive but there's some evidence that short periods are associated with lower DNA fragmentation, see<small>
:* {{Cite journal |last=Du |first=Chengchao |last2=Li |first2=Yi |last3=Yin |first3=Chongyang |last4=Luo |first4=Xuefeng |last5=Pan |first5=Xiangcheng |date=10 January 2024 |title=Association of abstinence time with semen quality and fertility outcomes: a systematic review and dose–response meta‐analysis |url=https://onlinelibrary.wiley.com/doi/10.1111/andr.13583 |journal=Andrology |language=en |volume=12 |issue=6 |pages=1224–1235 |doi=10.1111/andr.13583 |issn=2047-2919}}
:* {{Cite journal |last=Hanson |first=Brent M. |last2=Aston |first2=Kenneth I. |last3=Jenkins |first3=Tim G. |last4=Carrell |first4=Douglas T. |last5=Hotaling |first5=James M. |date=16 November 2017 |title=The impact of ejaculatory abstinence on semen analysis parameters: a systematic review |url=https://pmc.ncbi.nlm.nih.gov/articles/PMC5845044/ |journal=Journal of Assisted Reproduction and Genetics |language=en |volume=35 |issue=2 |pages=213 |doi=10.1007/s10815-017-1086-0 |issn=2047-2919 |pmc=5845044 |pmid=29143943}}
:* {{Cite journal |last=Ayad |first=Bashir M. |last2=Horst |first2=Gerhard Van der |last3=Plessis |first3=Stefan S. Du |last4=Carrell |first4=Douglas T. |last5=Hotaling |first5=James M. |date=14 October 2017 |title=Revisiting The Relationship between The Ejaculatory Abstinence Period and Semen Characteristics |url=https://pmc.ncbi.nlm.nih.gov/articles/PMC5641453/ |journal=International Journal of Fertility & Sterility |language=en |volume=11 |issue=4 |pages=238 |doi=10.22074/ijfs.2018.5192 |issn=2047-2919 |pmc=5641453 |pmid=29043697}}
:</small>
:for example. ] (] • ]) 02:12, 16 December 2024 (UTC)
:Mature sperm cells do not have ] capability.<sup></sup> Inevitably, as sperm cells get older, they will naturally and unavoidably be subject to more and more ]. Obviously, freshly produced spermatozoa will, on average, have less DNA damage. It is reasonable to assume that the expected amount of damage is proportional to the age of the cells, which is consistent with what studies appear to find. Also, obviously, the more the damage is to a spermatozoon fertilizing an oocyte, the larger the likelihood that the ] in the resulting zygote, which does have DNA repair capability, will be incomplete. The studies I've looked at did not allow me to assess how much this is of practical significance. &nbsp;--] 09:40, 16 December 2024 (UTC)


= December 16 =
If we add an low resistance air filter and then an air pump to compress the intake air of an fuel injected engine, will there be a increase in performance??Or do we need to tweak the ECU settings???


== ] ==
See ]--] 14:39, 10 November 2006 (UTC)


Thanks to those who answered my ], I think it should be added to a disambiguation page. If anyone wants to help me write that, reach out.
:Or see ]. And yes, I would assume you will want to increase fuel flow to match the increased air flow from the blower, if maximum power is your goal. ] 16:35, 10 November 2006 (UTC)


A sandpile seems disorganized and inert, but these are critically self-organizing. Do the frequency and size of disturbances on sand dunes and snowy peaks follow power law distribution?
::Whats the diff. Is there one?--] 16:37, 10 November 2006 (UTC)
] (]) 01:18, 16 December 2024 (UTC)
:Shouldn't this be at the Math Desk? <span style="font-family: Cambria;"> ] (])</span> 05:12, 16 December 2024 (UTC)
::If the question is not about the model mentioned in the heading but about the physical properties of sand dunes and snowy peaks, this here is the right section of the Reference desk. &nbsp;--] 08:51, 16 December 2024 (UTC)
:::I await a non-mathematical answer. <span style="font-family: Cambria;"> ] (])</span> 09:23, 16 December 2024 (UTC)
::::It depends is probably a fairly reasonable non-mathematical answer for these kinds of systems. For sand dunes anyway, sometimes avalanche frequency is irregular and the size distribution follows a power law, and sometimes it's close to periodic and the avalanches span the whole system. It seems there are multiple regimes, and these kinds of systems switch between them. ] (]) 09:35, 16 December 2024 (UTC)
:::::Thank you! I'm impressed this seems so casual, but surely you read this somewhere that might have a URL?
:::::] (]) 22:29, 19 December 2024 (UTC)


:Hi, this is an interesting and somewhat open question! A lot of work is done on these models but much less on careful analyses of real dunes. I did find that is freely accessible and describes some physical experiments and how well they fit various models. The general answer seems to be that the power law models are highly idealized, and determining the degree to which any real system's behavior is predicted by the model ahead of time is very difficult. Update: and it does include discussion of how well the model fits experiments.] (]) 17:21, 16 December 2024 (UTC)
:::Yes, a turbocharger is driven by the engine exhaust, which has the disadvantage of not providing much boost at low speeds, only at high speeds, while a blower is driven off the engine using a belt or chain. ] 16:41, 10 November 2006 (UTC)
::That dissertation is great!
::] (]) 22:30, 19 December 2024 (UTC)


== Polar night ==
::::Super answer! Thanks 8-)--] 16:46, 10 November 2006 (UTC)


Are there any common or scientific names for types of polar night? The types that I use are:
:::::Thanks (I'm not just blowing hot air, here). :-) ] 17:26, 10 November 2006 (UTC)
* ''polar night'' - meaning a day when sun's altitude remains below horizon entire day (there is no daylight at solar noon, only civil twilight), occurring poleward from 67°24′ north or south
* ''civil polar night'' - meaning a day when sun's altitude remains below -6° entire day (there is no civil twilight at solar noon, only nautical twilight), occurring poleward from 72°34′ north or south
* ''nautical polar night'' - meaning a day when sun's altitude remains below -12° entire day (there is no nautical twilight at solar noon, only astronomical twilight), occurring poleward from 78°34′ north or south
* ''astronomical polar night'' - meaning a day when sun's altitude remains below -18° entire day (there is no astronomical twilight at solar noon, only night), occurring poleward from 84°34′ north or south


These names were changed on ] article, and I wnat to know whether these named I listed are in use in any scientific papers, or in common language. (And I posted that question here and not in language desk because I think that this is not related to language very tightly.)
== please tell me about te project (TREFFIC PUMP) ==
--] (]) 18:56, 16 December 2024 (UTC)


:Some definitions at from the ]. ] (]) 22:55, 16 December 2024 (UTC)
hi,
::These seem to be generalizable as: X polar night is a period, lasting not less than 24 hours, during which the sun remains below the horizon and there is no X twilight. The specific definitions depend then on the specific definitions of ]/]/]. These can be defined with a subjective observational standard or with an (originally experimentally determined) objective standard. &nbsp;--] 10:36, 17 December 2024 (UTC)
i m nishant srivastava frm (bhopal) india.i m i B.teck final yera student of mechanical engg. i m working on a project TRAFFIC PUMP.. this project is basically use for water lifting.the hollow speed breaker of the material of rubber contain NON RETURN VALVE and this brekar are attached with pipe which also contain the NRV ..when the heavy vehical passes over the brekars then water lift in contineous ..so tell me mor abt that thank u
:::FWIW, I as a former amateur astronomer have never previously thought about the question of ''Polar'' twilight and night nomenclatures, but immediately and completely understood what the (previously unencountered) terms used in the query must mean without having to read the attached descriptions. {The poster formerly known as 87.81.230.195} ] (]) 16:34, 17 December 2024 (UTC)


= December 17 =
:Based on your description, the pumping action of a traffic pump is pretty much the same as that of a muscle pump in the human body. Go to Google Images and search for "muscle pump" or "skeletal muscle pump" to find illustrations of its action. You had a pretty understandable description of a traffic pump. Is there something specific that you don't understand? --] 14:01, 10 November 2006 (UTC)


== differential equations with complex coefficients ==
I can think of one negative: You can either put the rubber hose on top of the road, in which case it will wear out much more quickly, or imbed it in the road, which will cause the road to flex more, and wear out slightly more quickly. Also, being near the surface, the water would be subject to freezing, but I assume you would only use this system in portions of India where the temperature stays above freezing. ] 16:32, 10 November 2006 (UTC)


In an intro ODE class one basically studies the equation <math>\dot x=Ax</math> where x is a real vector and A is a real matrix. A typically has complex eigenvalues, giving a periodic or oscillating solution to the equation. That is very important in physics, which has various sorts of harmonic oscillators everywhere. If A and x are complex instead of real, mathematically the ODE theory works out about the same way. I don't know what happens with PDE's since I haven't really studied them.
:You need something like they used to use for picking up water by railway engines at high speed: a long trough full of water and a scoop on the engine. Whoosh!--] 16:35, 10 November 2006 (UTC)


My question is whether the complex case is important in physics the way the real case is. Can one arrive at it through straightforward coordinate transformations? Do the complex eigenvalues "output" from one equation find their way into the "input" of some other equation? Does the distance metric matter? I.e. in math and old-fashioned physics we use the Euclidean metric, but in realtivity one uses the Minkowski metric, so I'm wondering if that leads to complex numbers. This is all motivated partly by wondering where all the complex numbers in quantum mechanics come from. Thanks. ] (]) 22:54, 17 December 2024 (UTC)
::That would slow down the truck (and pull it off the road, if the scoop was on one side only). I believe the goal is to pump water, say for residential use, for "free" (not costing the trucks anything). ] 16:39, 10 November 2006 (UTC)


:Perhaps I don't understand what you are getting at but simple harmonic motion is xdot=j*w*x where w is angular frequency and j is i ] (]) 00:35, 18 December 2024 (UTC)
== how much electricity is produced ==
:If PDEs count, the ] and the ] are examples of differential equations in the complex domain. A linear differential equation of the form <math>\dot x=Ax</math> on the complex vector space <math>\mathbb{C}^n</math> can be turned into one on the real vector space <math>\mathbb{R}^{2n}</math>. For a very simple example, using <math>n=1,</math> the equation <math>\begin{bmatrix}\dot z\end{bmatrix} = \begin{bmatrix}i\end{bmatrix}\begin{bmatrix}z\end{bmatrix}</math> can be replaced by
::<math>\begin{bmatrix}\dot x\\\dot y\end{bmatrix} = \begin{bmatrix}0&-1\\1&0\end{bmatrix}\begin{bmatrix}x\\y\end{bmatrix}.</math>
:&nbsp;--] 01:11, 18 December 2024 (UTC)
:::Shouldn't this be at the Math Desk? It almost seems like the IP could be trolling, given the same question just above. <span style="font-family: Cambria;"> ] (])</span> 14:49, 18 December 2024 (UTC)
::::The question whether the complex case is important <u>in physics</u> the way the real case is, is not a maths issue. IMO the Science section is the best choice. I do not see another post that asks the same or even a related question. &nbsp;--] 21:51, 18 December 2024 (UTC)
:::::Just as above, I await a non-mathematical answer to this question. <span style="font-family: Cambria;"> ] (])</span> 07:01, 19 December 2024 (UTC)


Thanks all. Greglocock, your SHO example is 1-dimensional but of course you can have a periodic oscillator (such as a planetary orbit) in any orientation in space, you can have damped or forced harmonic oscillators, etc. Those are all described by the same matrix equation. The periodic case means that the matrix eigenvalues are purely imaginary. The damped and forced cases are where there is a real part that is negative or positive respectively. Abductive, of course plenty of science questions (say about how to calculate an electron's trajectory using Maxwell's equations) will have mathematical answers, and the science desk is clearly still the right place for them, as they are things you would study in science class rather than math class. Lambiam, thanks, yes, PDE's are fine, and of course quantum mechanics uses complex PDE's. What I was hoping to see was a situation where you start out with real-valued DEs in some complicated system, and then through some coupling or something, you end up with complex-valued DEs due to real matrices having complex eigenvalues. Also I think the Minkowski metric can be treated like the Euclidean one where the time coordinate is imaginary. But I don't know how this really works, and Misplaced Pages's articles about such topics always make me first want to go learn more math (Lie algebras in this case). Maybe someday. ] (]) 07:25, 19 December 2024 (UTC)
i would like to know about the amount of electricity that is produced when a peizoelectric material is used that is the relation between amount of elec produced and the dimensions of materials required????/


= December 18 =
See ]--] 14:38, 10 November 2006 (UTC)


== Why don't all mast radiators have top hats? ==
== Separating Mixtures ==


]Our ] article describes a device called a "top hat" which increases the range for mast radiators that can't be built tall enough.
I have a beaker full of ], ], and ]. I want to separate them from each other. The salt has dissolved in the water, and I assume the iron will be at the bottom of the beaker, and that it is finely ground up into a powder. I know that I should boil the mixture and separate the water via ], but how should I separate the remaining substances? What can I do to separate the salt and iron? Thanks for any help. --] 15:01, 10 November 2006 (UTC)


So, why would you bother building a mast radiator without a top hat? Couldn't you just build it shorter with the top hat, and save steel? ] (]) 15:00, 18 December 2024 (UTC)
:If the iron has already separated at the bottom, just pour off the water (keep it for the boiling stage to isolate the salt). You might then want to add distilled water to the iron, stir, wait for it to settle, then pour it off several more times to remove any remaining salt. If the iron particles were too small to settle, then a centrifuge would be needed. ] 16:12, 10 November 2006 (UTC)


:The main source cited in our article states, "{{tq|Top loading is less desirable than increased tower height but is useful where towers must be electrically short due to either extremely low carrier frequencies or to aeronautical limitations. Top loading increases the base resistance and lowers the capacitive base reactance, thus reducing the ''Q'' and improving the bandwidth of towers less than 90° high.}}"<sup></sup> If "reducing the {{serif|''Q''}}" is an undesirable effect, this is a trade-off design issue in which height seems to be favoured if circumstances permit. &nbsp;--] 21:41, 18 December 2024 (UTC)
::A ] or ] would be able to selectively remove iron particles from the solution in the beaker. Then boil off the water and only the salt is left. I expect that is why the problem specified a ferromagnetic material instead of some other material. ] 16:26, 10 November 2006 (UTC)


== Name of our solar system ==
::Pouring off the salt water is known as ]. —] 16:46, 10 November 2006 (UTC)


Is our star system officially called "Sol", or is that just something that came from science fiction and then became ubiquitous? ] (]) 22:06, 18 December 2024 (UTC)
:Why not use a ] to remove the iron particles. The remaining ] can be evaporated to get the water and salt separated. 8-)--] 16:30, 10 November 2006 (UTC)
:It's called the ], and its star is called Sol, from Latin via French. Hence terms like "solstice", which means "sun stands still" in its apparent annual "sine wave" shaped path through the sky. ←] <sup>'']''</sup> ]→ 23:31, 18 December 2024 (UTC)
:::Via French? According to the OED, it came direct from Latin.<sup></sup> &nbsp;--] 11:45, 19 December 2024 (UTC)}}
::::Old French plus Latin. ←] <sup>'']''</sup> ]→ 14:25, 19 December 2024 (UTC)
:::::Also in Old French, the word meaning "sun" was '']''. &nbsp;--] 23:42, 19 December 2024 (UTC)
::Let's say {{fact}} to that claim. The star is indeed called Sol if you're speaking Latin, but in English it's the Sun (or sun). Of course words like "solar" and "solstice" derive from the Latin name, but using "Sol" to mean "the Sun" does seem to be something from science fiction. --] (]) 06:04, 19 December 2024 (UTC)
:::"Sol" is occasionally used to mean the Sun by astronomers. I feel like it is used in contexts where it is necessary to distinguish our experience with the Sun here on Earth, such as sunsets, from more "sterile" aspects of the Sun one might experience off the Earth. <span style="font-family: Cambria;"> ] (])</span> 08:56, 19 December 2024 (UTC)
::::Being an astronomer myself, I don't think I've ever heard anyone use "Sol" outside of a science fiction context. --] (]) 09:06, 19 December 2024 (UTC)
::::::Scientific articles that use the term Sol; and . These are rather speculative but as I mentioned, the usage is for off-planet situations. <span style="font-family: Cambria;"> ] (])</span> 13:05, 19 December 2024 (UTC)
:::::Using Sol, Terra and Luna to refer to the Sun, Earth and Moon only happens if you write your entire article in Latin and in science fiction, not in regular science articles. They are capitalised though. Just as people write about a galaxy (one of many) or the Galaxy (the Milky Way Galaxy, that's our galaxy). The Solar System is also capitalised. ] (]) 10:38, 19 December 2024 (UTC)
::::::The article says "Sol" is the "personification" of the sun. Google Image the term "old Sol" and you'll see plenty of images of the sun with a face, not just Sci-Fi stuff. And "Luna" is obviously the basis for a number of words not connected with Sci-Fi. Lunar orbit, lunar module, etc. And the term "terra firma" has often been used in everyday usage. ←] <sup>'']''</sup> ]→ 11:34, 19 December 2024 (UTC)
::::::: And yet, if you ask 1,000 people "What's that big yellow thing up in the sky called?", you'll get 1,000 "the Sun"s and zero "Sol"s. Yes, in specialised contexts, Sol is used; but that doesn't justify saying our solar system's star "is called Sol" without any qualification, as if that were the normal, default term. It's not. -- ] </sup></span>]] 12:16, 19 December 2024 (UTC)
:::::::::And after you've gotten that response, ask them why it isn't the "Sunner System". And why a sun room attached to a house isn't called a "sunarium". And why those energy-gathering plates on some roofs are not called "sunner panels". ←] <sup>'']''</sup> ]→ 14:22, 19 December 2024 (UTC)
::::::::::What does that have to do with anything? The question was 'Is our star system ''officially'' called "Sol"?' (my emphasis). The answer is it is not. And that does not preclude other terms being derived from Latin ''sol'' (or, often enough, from Greek ''helios''), nobody denies that, it is irrelevant to the question. --] (]) 14:52, 19 December 2024 (UTC)
:::::::::::The problem is that the OP's question contains false premises. One is the question of what the "official" name is. There is no "official" name. It's the "conventional" name. And the second part, claiming that "Sol" comes from Sci-fi, is demonstrably false. ←] <sup>'']''</sup> ]→ 15:05, 19 December 2024 (UTC)
::::::::::::Then demonstrate (that the usage of "Sol" as a name for the Sun, in English, not its use to derive adjectives, originated outside of SF), with references. The original question does not even include any premises, with maybe the exception of "ubiquitous". --] (]) 15:18, 19 December 2024 (UTC)
:::::::::::::"Is our star system officially called "Sol" , or is that just something that came from science fiction and then became ubiquitous? ". And the wording of your own question, just above, does not make sense. ←] <sup>'']''</sup> ]→ 15:24, 19 December 2024 (UTC)
::::::::::::::Looking at Newspapers.com (pay site), I'm seeing colloquial references to "old Sol" (meaning the sun) as far back as the 1820s. No hint of sci-fi derivation. ←] <sup>'']''</sup> ]→ 15:32, 19 December 2024 (UTC)
:::::::::::::::Great! Well done. --] (]) 15:41, 19 December 2024 (UTC)
::::::::::::::::Feel free to box up this section. ←] <sup>'']''</sup> ]→ 15:52, 19 December 2024 (UTC)
:::::::::::::The 1933 OED entry for ''Sol'', linked to above, gives several pre-SF uses, the earliest from 1450. &nbsp;--] 23:48, 19 December 2024 (UTC)
::::::::::::::Yes, of course, but that's not surprising, is it? 15th century humanists, astrologers and pre-Victorian poets liked to sprinkle their texts with Latin words. But I don't think this is what the question is about. It's a matter of context, but it should be up to OP to clarify that. --] (]) 08:48, 20 December 2024 (UTC)
:::::::::::::::It's not surprising, but the discussion was not whether the use of ''Sol'' in English texts is surprising, but whether it originated outside of SF. &nbsp;--] 10:52, 20 December 2024 (UTC)
::::::::::::::::In my view, the question has a clear scifi bent, and that particular usage ("Where shall we go for our vacation? Alpha Centauri or Sol?") does not originate in the 15th century. The word is much older, of course it is, but the usage is not. In the 15th century people didn't even know that the Sun is just an ordinary star and could do with a particular name to distinguish it from the others. The connotations of ''sol'' were vastly different from what they are today and from what is implied in OP's question. Incidentally, the ] doesn't even define a name , although they recommend using capitalised "Sun". Certainly no "Sol" anywhere. --] (]) 12:04, 20 December 2024 (UTC)
::::::::{{small|Does that make it a Sol-ecism? ] (]) 12:19, 19 December 2024 (UTC)}}
:::::::::<small>More like a ]. Meaning a factory where suns are made. From Sol = sun, and ipso = facto. Thus endeth the entymogology lesson for today. Go in peace to love and serve whomsoever. -- ] </sup></span>]] 19:37, 19 December 2024 (UTC) </small>


== Mountains ==
::I would like to thank you all for your quick responses. Thanks a bunch! =] --] 18:50, 10 November 2006 (UTC)


Why there are no mountains on Earth with a height above 10,000 m? As the death zone is about at 8,000 m, and above 19,000 m, there is an Armstrong limit, where water boils at normal human body temperature, it is good that there are no more mountains higher than 8,000 km than just 14, but if there were hundreds of mountains above 9,000 m, then these were bad to climb. If there were different limits for death zone and Armstrong limit, would then there be possible to have higher mountains? I have just thought that, it is not a homework? --] (]) 22:29, 18 December 2024 (UTC)
:::To remove all the iron you are gonna have to increase the pH of the water to facilitate precipitation of iron oxide (some will be colloidal, but it will dry out on the filter eventually). Since the iron oxide will not be ferromagnetic, a filter will be more useful than a magnet to separate iron from the salt water (which may or may not be brine, the poster did not indicate the amount or kind of salt). Distillation is probably the easiest way to then resolve the salt water. ] 18:55, 10 November 2006 (UTC)


:There are ] that are over 20km high. Given that some of those are on airless worlds, I don't think the air pressure has any bearing on it. ] (]) 22:57, 18 December 2024 (UTC)


:Multiple sources from web searching suggest the ''theoretical'' maximum height for mountains on Earth is around 15,000 m – the limiting factor is ]; the higher (therefore more voluminous) a mountain is, the more its weight causes the crust beneath it to sink. The actual heights of mountains are a trade-off between how fast tectonic movements can raise them versus isostatic sinking ''and'' how quickly they are eroded, and tectonic movements do not last for ever. See also ]. {The poster formerly known as 87.81.230.195} ] (]) 00:25, 19 December 2024 (UTC)
:Does anyone else think this sounds suspiciously like a homework question? ] 21:55, 10 November 2006 (UTC)
::And erosion goes faster as the mountain gets higher, in particular when it's high enough to support glaciers – one reason why mountains can get higher on an airless world. Now it gets interesting for a mountain high enough to reach into the stratosphere, as it would be too dry to have anything but bare rock. I suppose it would locally raise the tropopause, preventing that. ] (]) 11:13, 19 December 2024 (UTC)


= December 19 =
::To me, it sounded like they wanted help doing a chem lab, in which case, giving them a few pointers is OK, so long as they actually do the lab work themselves. ] 22:47, 10 November 2006 (UTC)


== Does human DNA become weaker with each generation? ==
=== Rusting iron in water ===


As with photocopying something over and over, the text becomes less clear each time.
Why is there iron oxide in the mix. The OP didnt say there was/. And of course we assume the salt is NaCl--] 20:25, 10 November 2006 (UTC)


Does human DNA become weaker with each generation? ] (]) 21:22, 19 December 2024 (UTC)
:Maybe your chemistry is a bit rusty, but small iron particles in saltwater would rapidly oxidize. ] 21:54, 10 November 2006 (UTC)
:Sure, DNA replication is not perfect, although ] reduces the error rate to about 1 mistake per 10<sup>9</sup> nucleotides (see our article on ]). But that is per generation of cells, not of the whole organisms. Many mutations will be neutral in effect (because much of our DNA is redundant), some will be deleterious, and a few might be advantageous. It is the process of natural selection that hinders the spread of deleterious mutations: sometimes this aspect is called ]. One thus usually expects a stable ] over time rather than that "DNA becomes weaker with each generation". Medical science is reducing the selection pressure against some mutations, which consequently may become more common. One of the problems for asexual organisms is referred to as ]; assuming that reverse mutations are rare, each generation has at least the mutational load of its predecessor. In contrast, in sexual organisms ] generates the variation that, combined with selection, can repair the situation. Sexual organisms consequently have a lighter genetic load. ] (]) 22:42, 19 December 2024 (UTC)
::So ] won't work properly in case of ] ? ] (]) 23:16, 19 December 2024 (UTC)
:::The larger the degree of inbreeding, the larger the chance that deleterious traits are expressed. But this very expression of traits leading to decreased biological fitness of their bearers is what actually enables purifying selection in the longer term. &nbsp;--] 23:36, 19 December 2024 (UTC)
::::@] so ] won't stop these deleterious traits to get expressed? ] (]) 14:11, 20 December 2024 (UTC)
:::::No, this is not an issue of ]. The genes involved are faithfully reproduced and passed on from generation to generation. &nbsp;--] 15:53, 20 December 2024 (UTC)
:Or stronger e.g. "", and those guys live for centuries and have much more DNA than us. ] (]) 15:21, 20 December 2024 (UTC)
::@] If not due to DNA damage, why do babies from inbreeding appear like DNA-damaged species? ] (]) 17:29, 20 December 2024 (UTC)
:::Inbred offspring of species that normally outcross may show abnormalities because they are more likely than outcrossed offspring to be ] for ] that are deleterious. In individuals that are heterozygous at these loci, the recessive alleles will not be expressed (because the other wild-type dominant allele is sufficient to do their job adequately). See our article on ]. ] (]) 19:26, 20 December 2024 (UTC)


== Larvae going south ==
Not without an oxidiser!--] 03:46, 11 November 2006 (UTC)


In a novel I've just finished ('']'' by ]) he writes:
:There's always dissolved air in water. ] 08:34, 11 November 2006 (UTC)
* '' leave the body in an orderly fashion, following each other in a neat procession that always heads south. South-east or south-west sometimes, but never north. No-one knows why''.


The author has done considerable international research on the science of forensic identification of decayed bodies and I assume his details can be trusted.
:I think the iron does not have time to oxidise in salt water without access to free O2. I thought the ions in water were OH- and H+ and therefore no source of free oxygen except for the dissolved air. But I could be wrong. 8-? OK lets assume the water had been boiled to remove dissolved oxygen 8-)--] 18:32, 11 November 2006 (UTC)


I've looked online for any verification of this surprising statement, but found only , which seems to debunk it.
::If you boil the water in air, you still end up with some dissolved oxygen in the water. You would need to boil it in some other gas, such as nitrogen, to remove all the dissolved oxygen. ] 20:51, 11 November 2006 (UTC)


Is there any truth to this? -- ] </sup></span>]] 23:38, 19 December 2024 (UTC)
:::OK You win I give up 8-)--] 21:11, 11 November 2006 (UTC)


:Can't speak to its truth, but . . .
See on rusting. Its very interusting 8-)
:* Does Beckett state this in his own auctorial voice (i.e. as an ])? If so, he might be genuinely mistaken.
:* The book was published nearly 20 years ago, what was the accepted wisdom ''then''?
:* What specific species (if any) is the book describing? – your linked Quora discussion refers only to "maggots" (which can be of numerous species and are a kind of larva, but there are many others, including for example ]).
:*Alternatively, if the statement is made by a character in the book, is that character meant to be infallible, or is he portrayed as less than omniscient, or an ']'?
:Regarding the statement, in the Northern hemisphere the arc of South-east to South-west is predominently where the Sun is found well above the horizon, the North never, so the larvae involved might simply be seeking maximum warmth or light. {The poster formerly known as 87.81.230.195} ] (]) 02:18, 20 December 2024 (UTC)


:: This appears in the very first paragraph of Chapter I, which starts out:
== Cancer ==
::* ''A human body starts to decompose four minutes after death. Once the encapsulation of life, it now undergoes its final metamorphoses. It begins to digest itself. Cells dissolve from the inside out. Tissue turns to liquid, then to gas. No longer animate, the body becomes an immovable feast for other organisms. Bacteria first, then insects. Flies. Eggs are laid, then hatched. The larvae feed on the nutrient-rich broth, and then migrate. They leave the body in an orderly fashion ...'' (then the quote above completes the paragraph).
:: It's not until para 2 that he starts talking about any human characters, and not until para 4 that he invokes the first person.
:: That's as much as I know. But I find it hard to believe he'd just make up a detail and put it in such a prominent place if it could so easily be debunked if it were not true. -- ] </sup></span>]] 02:39, 20 December 2024 (UTC)
:::I wonder how they would measure the migratory path of maggots within a sealed coffin. ←] <sup>'']''</sup> ]→ 02:51, 20 December 2024 (UTC)
:::: The context of the novel is about finding decaying corpses that have been dumped in a forest. No coffins involved. -- ] </sup></span>]] 06:08, 20 December 2024 (UTC)
::::::], see also ] research facilities. ] (]) 13:44, 20 December 2024 (UTC)
:::::Could it be that the larvae are setting off in search of another corpse? The prevailing wind in the UK is from the south-west, so by heading into the wind they won't be distracted by the frangrance of the one they've just left. ]|] 09:30, 20 December 2024 (UTC)


If you can, have a look at 'Heinrich, Bernd. “Coordinated Mass Movements of Blow Fly Larvae (Diptera: Calliphoridae).” Northeastern Naturalist, vol. 20, no. 4, 2013, pp. N23–27. JSTOR, http://www.jstor.org/stable/43288173.' Here are some extracts
How does cancer kill? It can't be just because there's an extra lump in the body. Or can it?... ] 15:13, 10 November 2006 (UTC)
* On the fourth day, after a cooling night with dew on the grass, a stream of tens of thousands of larvae exited from beneath the carcass within 1 h after sunrise, and proceeded in a single 1-2-cm-wide column directly toward the rising sun...
* However, in this case, the larvae left at night, within 1 h after a cloudburst (at 21 :00 hours). But, unlike before, this nocturnal larval exodus in the rain was diffuse; thousands of larvae spread out in virtually all directions over an 8 m2area. Apparently, the sudden moisture had cued and facilitated the mass exodus, but the absence of sun had prevented a unidirectional, en masse movement.
* However, on the following morning as the sun was starting to illuminate the carcass on the dewy grass, masses of larvae gathered at the east end of the carcass at 07:00 hours. In one half hour later, they started streaming in a column directly (within one degree) toward the rising sun, and the carcass was then nearly vacated.
It goes on. Maggot migration appears to be a bit more complicated than the novel suggests. ] (]) 09:39, 20 December 2024 (UTC)
I suppose you could try to address it from the other direction and look at the technology your average maggot has access to in terms of light detection, heat detection, olfactory systems, orientation in magnetic fields (like many arthropods) etc. They presumably have quite a lot of tools. ] (]) 10:13, 20 December 2024 (UTC)


:If orderly migrating maggots tend to move towards the sun, they should display a northward tendency in Oztralia. &nbsp;--] 10:31, 20 December 2024 (UTC)
:In some cases, yes, because the lump puts pressure on some vital organ, like the heart or lungs or a blood vessel, but that's rather rare (and easily remedied with surgery). More commonly, the cancer cells destroy some system (like the immune system, allowing other diseases to run rampant, or the lungs, depriving the body of oxygen). ] 16:07, 10 November 2006 (UTC)
:: Maybe, but the novel is set in England.
:: I must say, as soon as I read the quoted para for the first time, my immediate thought was that it might have something to do with the magnetic field of the earth. -- ] </sup></span>]] 10:42, 20 December 2024 (UTC)
:::Prime suspect might be the Bolwig organ, the photoreceptor cluster many fly larvae have. ] (]) 10:49, 20 December 2024 (UTC)
:::Obviously, Jack, you need to create a corpse, place it in a nearby forest, and carefully observe which way the maggots go. For Science! And Literary Criticism! {The poster formerly known as 87.81.230.195} ] (]) 21:01, 20 December 2024 (UTC)


= December 20 =
::How does it destroy the immune system or lungs? ] 16:51, 10 November 2006 (UTC)


== Winter solstice and time of sunrise? ==
::Generally it kills in three ways: displacement, compression, or metabolism. Some cancers, leukemia comes to mind, can become so widespread throughout the body that they actually replace the cell type they are derived from. In some kinds of leukemia, the cancerous bone marrow replaces all of the normal marrow in the bones, leaving no healthy cells left to produce blood cells. Other times a tumor can grow large enough that is pushes other sensitive organs out of the way or occludes important blood vessels. This usually happens with faster growing cancers, and is most prominent withing the head, where there is limited space to begin with. For the most part, though, cancer kills through "overeating". Cancer cells metabolize and grow vey quickly. Much like teenagers, they eat everything in sight and don't actually do much work other than growing. This leaves other cells in the area hungry, and eventually leads to their death. You might note that these things are not mutually exclusive, and also that benign tumors are capable of the compression and overmetabolism too. ] 16:36, 10 November 2006 (UTC)


How is it that despite December 21st supposedly being the shortest day of the year, sunrise here happens later and later until December 26 and only on January 05 starts to turn around to occur earlier and earlier. On December 25 it takes place at about 08:44, between December 26 and January 04 it takes place at about 08:45, and on January 05 it takes place again at about 08:44. (Google rounds out the seconds). Is it Google's fault? Is it everywhere the same? Confused in Brussels, Belgium. ] (]) 12:06, 20 December 2024 (UTC)
:::How can it displace other cells? Won't the healthy cells keep dividing into more, functioning cells as usual, even if there are cancerous cells dividing as well? As for compression, do cancer cells grow too fast to constantly surgically remove them? That is, is the recovery period for brain surgery for cancer removal longer or shorter than the period at which cancer cells (if they re-emerge) might become dangerously large again? As for metabolism, couldn't that problem be solved by giving the patient an extremely hyperglycemic diet, perhaps through TPN? ] 16:51, 10 November 2006 (UTC)
:The pertinent article is ], start with the section ]. The details are not that simple to understand, but it's basically due to the ellipticity of Earth's orbit and its axial tilt. --] (]) 12:22, 20 December 2024 (UTC)
::Also note that sunset begins to be later on 22 December so that the time between sunrise and sunset is a few seconds longer than on 21 December (3 seconds longer on 22/12/24 in Brussels according to ). ] (]) 13:33, 20 December 2024 (UTC)
::Also see ]. The obliquity of the ecliptic (that is, the Earth's axial tilt) is the main component and hardest to understand. But the idea is that the time when the Sun is exactly south (that is, the true noon) moves some minutes back and forth throughout the year and it moves quite rapidly to later times in late December. ] (]) 19:05, 20 December 2024 (UTC)


== Three unit questions ==
:::::Great questions. Displacement is usually secondary to the the metabolic outperformance. Often vascularization of the new growth is more extensive (though less organized) than the normal tissues, which allows the cancer cells to grow faster, and which shunts much of the nutrition to the tumor. As a result, the normal cells die off faster and grow slower, and become outnumbered. In fact tumor cells, even the ones that grow exceedingly fast, can be removed if they are detected, and cerainly don't grow faster than a scalpel. This is why benign tumors are so named. However, if the margins of the tumor are very complicated or if they metastisize, either by "blending" into nearby tissue or by travelling through the circulatory or lymph systems, they can be more difficult to remove surgically. Radiation therapy can help kill cancer cells selectively in a situation such as blending where the tumor is in a known area with blurry borders, and chemotherapy can help destroy cancer cells which have metastasized. Unfortunately a hypernutritive diet won't help much because the nutrition deficit is more of a local problem than a body-wide one. ] 18:46, 10 November 2006 (UTC)


# Why territorial waters are defined by nautical miles instead of kilometers?
::::::Awesome info, and you picked up on my hyperglycemic->hypernutritive mistake, great. Well, thanks! :D ] 22:13, 10 November 2006 (UTC) <- me ] 22:14, 10 November 2006 (UTC)
# Why GDP is usually measured in US dollars rather than euros? Euro would be better because it is not tied into any country.
# Are there any laws in United States that are defined by metric units?
--] (]) 23:30, 20 December 2024 (UTC)
:#There were nautical miles in use before there were kilometers.
:#There were US dollars in use before there were Euros.
:#Yes.
:The questions all reduce to Why can't millions of people make a change of historically widely accepted units that continue to serve their purpose, and convert to different units that would have no substantive difference, because someone has an opinion. ] (]) 00:52, 21 December 2024 (UTC)
::Do any people use metric units in marine and air navigation like "The ship is 10 kilometers from the port", "The plane is 10 kilometers from the destination? And is there any European country with metric flight levels? --] (]) 07:22, 21 December 2024 (UTC)
:::Inland shipping (rivers, canals and lakes) in Europe (except the UK) is fully metric. Ships going for example ] – ] may have to switch units along the way. Gliders and ultralight aircraft in Europe often use metric instruments and airport dimensions are also metric (including runway length). Countries are free to define their territorial waters in whatever way they deem fit, so with nautical miles having no legal status in a fully metric country, they may define their territorial waters as extending 22224 metres. ] (]) 11:23, 21 December 2024 (UTC)
::::Our ] article says: {{xt|"In 1929 the international nautical mile was defined by the First International Extraordinary Hydrographic Conference in Monaco as exactly 1,852 metres (which is 6,076.12 ft). The United States did not adopt the international nautical mile until 1954. Britain adopted it in 1970..."}}
::As the US customary units are actually defined in terms that relate them to metric units, any US law based on measurements is technically defined by metric units.--] (]) (]) 01:55, 21 December 2024 (UTC)
:::The US dollar has been the world's dominant ] for about 75 years. As for the metric system in the US, it is standard in scientific, medical, electronics, auto manufacturing and other highly technical industries. By law, all packaged foods and beverages have metric quantities as well as customary quantities. See ]. ] (]) 02:28, 21 December 2024 (UTC)
The Wikipaedia article on the Nautical Mile talks about how the term originated, it was originally defined in terms of latitude not as a number of meters ] (]) 10:03, 24 December 2024 (UTC)


= December 24 =
::::These answers have also hit on one of the primary reasons why chemotherapy is effective. The chemical poison kills all cells but becuase the cancer cells abosrb more poison in a shorter time, they receive a lethal does sooner. The idea is that they will die before the non-cancer cells. --] 05:13, 11 November 2006 (UTC)


== Why so big? == == Unknown species of insect ==


Am I correct in inferring that ] this guy is an ]? I was off-put by the green head at first, but the antennae seem to match. ''']]''' 03:00, 24 December 2024 (UTC)
Why has been the dinosors so big? Is it a thing what can be explained from evolution?


(reference: https://www.genesdigest.com/macro/image.php?imageid=168&apage=0&ipage=1)
] 17:01, 10 November 2006 (UTC)


:<s>It looks like one of the invasive ]s that happens to like my blackberries in the summer.</s> ] (]) 13:11, 24 December 2024 (UTC)
:There are certain advantages to size, like being able to defend yourself from a smaller predator or, if you are the predator, being able to kill your prey. This would naturally lead to an infinite race to be the largest, unless there were also some advantages to being small, which there are. Food requirements are reduced, the ability to hide is better, etc. However, to explain why land animals used to be much larger than they are now, one of these advantages or disadvantages must have changed from the time of the dinosaurs until now. Note that sea animals, namely whales, are the largest they have ever been right now, so this change apparently does not apply to the sea. One change I'm aware of is that oxygen levels in the air used to be higher, as demonstrated by air bubbles stuck in amber from the time of the dinosaurs. Our current lower oxygen levels would limit the size of animals, as present dinosaur-sized animals would need to move quite slowly or have greatly increased lung capacities relative to the sizes of their bodies. The oxygen level in water is related to that in the air, although sea mammals don't use the oxygen in the water, but rather breathe air. Also note that different calculations come into place, as sea mammals have reduced energy requirements. This is due to more efficient locomotion and thermal control mechanisms. ] 17:20, 10 November 2006 (UTC)


::I would say not necessarily a Japanese beetle, but almost certainly one of the other ] beetles, though with 35,000 species that doesn't help a lot. Looking at the infobox illustration in that article, 16. & 17., "]" looks very similar, but evidently we either don't have an article or (if our ] article is a complete list) it's been renamed. {The poster formerly known as 87.81.230.195} ] (]) 14:18, 24 December 2024 (UTC)
:Also note that not all dinosaurs were very big. ] 21:51, 10 November 2006 (UTC)


:::Yes, it's not the Japanese beetle for this beetle appears to lack its white-dotted fringe although its condition is deteriorated. Its shape is also more or less more slender; and not as round. ] (]) 15:02, 24 December 2024 (UTC)
:How long did it take for dinosaurs to grow so big? The rise of the dinosaurs started 20 million years after the ] and they had 160 million years to evolve. The ] that wiped ''them'' out occurred 'only' 65 million years ago. So maybe 'we' just need more time. But also, mammals require much more energy, and thus much more food, per weight because they are warm blooded and need to keep their temperature up all the time. So a viable population will require a much larger area. So given the same habitat size, reptiles can afford to grow larger. Another thing is how large the habitat can be. If a species specialises more, it will have a smaller habitat and can therefore not grow as large. Maybe mammals have a stronger tendency to specialise. Note that I know little about the subject and am just doing some educated guessing. :) ] 08:21, 11 November 2006 (UTC)
::Well, according to ], dinosaurs ''were'' warm blooded. ] 08:33, 11 November 2006 (UTC)


:Perhaps it is the ] ]. Shown . ] (]) 16:09, 24 December 2024 (UTC)
== How are refusals to participate handled on surveys ? ==
::That looks like easily the best match I've seen so far, and likely correct. {The poster formerly known as 87.81.230.195} ] (]) 17:09, 24 December 2024 (UTC)


= December 25 =
The surveys I see typically have a 3% margin of error. However, I can't believe that over 97% of the people they ask to participate agree, especially if not compensated. I'm guessing they just assume that the participants are representative of the population, while I most definitely would not. That is, if 10% refused, I would add that to the margin of error to get a 13% margin (12.7%, technically). For example, in the recent US elections, most of those who refused to participate in surveys may well have been conservatives disgusted with the Bush administration and the numerous financial and sexual scandals of Republican Congressmen. Thus, their non-participation would bias the survey. Also note that surveys where participants self-select (say a web site with a link to take a survey) have a much higher rate of non-participation, which is unknown, as the number of people who read the ad and decide whether to participate is unknown. How are these issues handled by statisticians ? ] 17:07, 10 November 2006 (UTC)

: The question is a good one, and I know the answer only to the seond part. Survey where the participants self-select, such as in your example of the web site, are either totally useless or only an extremely rough indicator. Professionals don't take them seriously as far a I am aware. (Actually: As I am a scientist working for a university I occasionally get request to form out web surveys from within the university. These are, however, usually parts of master theses, typically by students of economy or social sciences, and I always have the feeling that the results will be enough to earn a degree but not to publish a paper. Or, worse, the survey originates from some internal project office within central adminstration and tries to assess some work-place related issues in order to burn some money for pretended actionism.) For properly random-sampled survey, I imagine that the bias problem is the reason why the precentage of refusals are always given. Maybe you are supposed to form your own opinion how this contributes to the error. As far as error figures are concerned: in German newspaper I hardly see them given. ] 20:12, 10 November 2006 (UTC)

::I suspect the university has you do the surf\veys so they can imply that they are "scientific surveys". If I were you, I would insist on a big fat disclaimer on all those surveys saying "This is '''NOT''' a scientific survey, and is only to be used for entertainment purposes". ] 20:57, 10 November 2006 (UTC)

In a related question, how is lying on the survey handled ? Is any margin added to account for the percentage which can be expected to lie ? If niether of these are accounted for, I would expect survey results to be highly inaccurate. In cases where they can actually be checked, like voter surveys, I would expect many election results to fall outside the margin of error. ] 21:02, 10 November 2006 (UTC)

:The ] on a survey, ''by definition,'' covers only the ]. If you ask 1000 people out of a much larger population about something, your error due to the fact that you didn't ask the entire group is going to be about 3%. ] are not accounted for in the margin of error, simply because that's how the margin of error is defined. As such, the margin of error of a survey is not necessarily a good measure of how far off the survey is actually likely to be from the true value you would get if you asked everyone, and everyone responded truthfully. ] 23:30, 10 November 2006 (UTC)

::In that case, the term is thoroughly misused by the public, and those doing amateur surveys, to mean the total maximum error. ] 02:32, 11 November 2006 (UTC)

There are lots of corrections and that is why there are lots of polling organizations. The first correction has already been touched on and that is a sample of the real population will always have a margin of error. But as polls develop and they are compared to the actual results, the errors associated with systemic bias are corrected from historical analyses. For example, it is known polls are more likely to garner a response from Democrats than from Republicans. This is true for both phone polls and exit polls. Since pollsters know this, they correct for it. There is also differences based on age, gender, education, region of the country, etc. These are all put into a fudge factor that they use to weight the poll. This is why Zogby and Gallup get different results even though they ask the same question: they have different weighting factors. It is also how exit polls can exceed the margin of error. --] 02:54, 11 November 2006 (UTC)

=== US Congressional Election results vs Voter Surveys ===

Is there any analysis of how accurate survey results were, in relation to the actual election results ? I'd be interested to know how well they did at predicting the results. ] 21:07, 10 November 2006 (UTC)

At you can scroll down to "Rudimentary statistics" and see a nice explanation of statistical sampling theory. The site, although somewhat partisan in philosophy, also presents a nice compilation of all the published scientific polls regarding President Bush's approval rating over time, so you can get an idea of the central tendency and see which polls tend to produce higher and lower approval ratings, and compare his ratings to past 2 term presidents. One key point is adjustment: I will make up illustrative numbers: a polling organization may assume in their population model that the voters are, say 55% Democrat and 45% Republican. In a 3 day phone survey of 1000 respondents, they may have found 70% of those who answered the (random) phone call and completed the survey said they were Democrats and 30% said they were Republicans. A high % of the Republicans say they approve of Bush and a high % of Democrats will say they disapprove. Rather than reporting the actual observed percentages, the pollster is likely to adjust the observed Dem/Rep proportions to the ones espected, before computing the overall approval rating. They will make similar adjustments for black vs white, male vs female, to adjust for the fact that, say Republicans don't do phone surveys, or at work, or only use cel phones, or whatever skewed the sample percentages away from the population percentages. Thus it is an art as well as a science, and is hardly ever a pure exercise of random sampling. One pollster for a party admitted to absolute fraud: if the person hung up, the surveyor just made up responses. Amazingly the daya came out favorably for the party funding the poll. ] 05:59, 11 November 2006 (UTC)

== Mileage equivalent of raising a car. ==

I was wondering how far an average car might travel using the same fuel burned to get to the top of a 20m car park. Petrol has an energy content of 32MJ/l so assuming 8 miles per litre, 4MJ per mile. 1 ] is the minimum energy to raise 1kg 10 cm, so assuming a 400kg vehicle, 80,000J would be required. Engine efficeny is 30% so this becomes 240,000 J, if we say 250,000J we get a distance of 1/16 mile which is approximately 100m. This seems silly, implying cars use only five times as much energy to move "up" as to move "along". Have I slipped a decimal point somewhere? ''] ]'', 17:40 ] ] (GMT).

:HAve you taken into account the air resistance and rolling friction and other losses in climbing the hill? THe hill probably takes the sum of the two energies you calculated assuming the same speed of travel.--] 17:52, 10 November 2006 (UTC)

I've thought about this issue myself, as I used to drive 15 minutes to get to a parking structure, then I would drive another 15 minutes within the structure, waiting in lines and searching for an open space. I'm sure most of my gas was wasted in that damn thing. If there was a way to reclaim the gravitational potential energy, say by ], much of this waste could be eliminated. ] 18:32, 10 November 2006 (UTC)

:Cos is ]--] 18:35, 10 November 2006 (UTC)

:Only five times as much? Ideally, it would be infinitely much more, because when lifting a car, actual work is done in the sense that there is a difference in the energetic state. When moving a car horizontally, that is not the case. So if there would be no resistance to overcome and the acceleration at the start of the trip would be regained during breaking at the end, there would be no consumpton of energy at all. That cars still use one fifth of the energy for horizontal transpor tis an indication of how horribly inefficient they are. Take a very smooth cannon ball. How much energy does it take to lift it to a height of 2 m? And how much energy would it take to make it roll 2 m over a smooth surface? For something closer to home, take a baseball. You'd have to give it a really minor push (with your pinky) to prevent it rolling more than 2 m. And the major reason it will stop at all is that the surfaces aren't smooth enough. ] 08:50, 11 November 2006 (UTC)

::And an idling car uses an infinite amount of energy per distance moved ! ] 20:31, 11 November 2006 (UTC)

:::Yes thats why you should turn off your engine whilst waiting.

== Is a solution defined as a mixture in chemistry ==

Prompted by an earlier question I wonder: Is a ] defined as a ] or a ] in chemistry?--] 18:40, 10 November 2006 (UTC)

:Why don't you read the article you linked to, ]. First sentence. ] 18:57, 10 November 2006 (UTC)

:I did. It is confusing as it mentions homogenous mixtures.--] 19:02, 10 November 2006 (UTC)

:Does the first sentence of ] help? Could you prepare salt-water solutions in which you alter the the ratio of the components? ] 20:07, 10 November 2006 (UTC)

::OK a solution appears to be a mixture . THanks for the solution to this problem 8-)--] 20:15, 10 November 2006 (UTC)

:::"''There are three different types of mixtures: homogeneous mixtures (also called solutions), heterogeneous mixtures, and colloidal dispersions.''" from ] --] 03:04, 11 November 2006 (UTC)

== Blindness & Nothingness ==

One can be fairly sure that it is nearly impossible to ''imagine'' nothingness. For when you are ''thinking'' of nothingness, you're still ''thinking'' of something. But nevertheless, I've tried. Today, I was closing my eyes, meditating, and I was trying to imagine what it would be like to be blind. Here is my question: does the mind of a blind person interpret the lack of vision as a sort 'blackness' - much like I do when I close my eyes - or does the mind of a blind person interpret the lack of vision as a complete absence of anything (i.e. no blackness, just nothing)? - ] ] (, ) 18:42, 10 November 2006 (UTC)

:There is actually a way to imagine nothingness (well my nothingness is actually black). As for being blind IDK--] 19:55, 10 November 2006 (UTC)

: Don't know either. However, I remember an interesting piece of news. A museum made a completely dark room, where visitors has to use their tactile sense to orient themselves. The idea was to give seeing people an impression of what being blind was like. A spokesman of some German association of blind people commented that he considered the setup a bad idea: after all, a seeing person would feel frightened and disoriented due to the vivid impression of the blackness. From these feelings, the spokesman argued, the visitor would get a way too negative idea of how blind people experience the world, as under normal circumstances they feel as normal (i.e., secure and oriented) as normal people do, and they do not expeience any blackness or lack of sensation as long as their other sense provide usual input. ] 20:20, 10 November 2006 (UTC)

::Very interesting. - ] ] (, ) 21:49, 10 November 2006 (UTC)

:I think it depends whether the person has been blind from birth or could once see and has been blinded. See also ]. —] 20:30, 10 November 2006 (UTC)

:I expect the latter. Consider a curious bat wondering what it's like for people who don't have a sonar-type sense. Do people specifically notice that they don't have this sense? Or consider the similar question a monkey might ask of people without a prehensile tail: do people try to move their tail to grab things only to constantly notice they don't have a tail? Essentially animals (humans included) have a set of inputs and outputs, if you like, that we learn to use at the appropriate times. If you've never had a particular sense or limb, you'll never feel inclined to use it or to even notice it isn't there (obviously the case of a person who has only recently lost their sight is a different matter), I expect. ] (]) 22:53, 10 November 2006 (UTC)

If they were born blind, they would have never devolved the neurons to interpret vision in the first place. Check out this article --] 23:09, 10 November 2006 (UTC)

A blind person wouldn't be "thinking of nothingness", they'd still build up an 'internal' interpretation of what the world is like based on their other senses.

Trying to "blank" your mind and not have any thoughts at an instant is a completely different thing. Complete clearing of the mind of thoughts is supposed to be a skill learnt by some forms of meditation, and supposedly not easy either. I personally can't imagine how someone could be consicencly awake and not have any thoughts (heck...your mind's thinking and working even when you're not consciencely awake), but some people (like buddist monks and stuff) claim they can completely clear their mind of thoughts during meditation. --] 03:04, 11 November 2006 (UTC)

YEs its not easy. You let thought come and let them go with out holdnig on to them. Finally thoughts are more rare and eventully stop--] 03:43, 11 November 2006 (UTC)

:If you are what you think then to stop thinking would mean to stop existing. Think on that (or not). ] 18:17, 11 November 2006 (UTC)

::I dont think so!--] 18:24, 11 November 2006 (UTC)

== Plasma ==

How Hot would it have to get for water to turn into a plasma and if it was hot enough would it actually be Hydrogen and Oxygen gas?] 20:31, 10 November 2006 (UTC)

:Yes, it would split into oxygen and hydrogen first. ] 20:45, 10 November 2006 (UTC)

::And then into a lot of ions?--] 20:54, 10 November 2006 (UTC)
Thank You StuRat I thought that,but anyways is there a formula for how much volume, lets say a liter of water, would take up when it is turned into a gas?

:::Depends on the volume its allowed to expand into. PV/T is a constant. I think ]s act like a gas.--] 21:00, 10 November 2006 (UTC)

::::Plasmas definitely don't follow the ] laws, but you can use them for ]s. —] 21:07, 10 November 2006 (UTC)

::Im sure my answers will be sufficiently accurate for the purposes of the OP 8-)--] 21:09, 10 November 2006 (UTC)

:According to my calculations, at atmospheric pressure, water is halfway dissociated into H<sub>2</sub> and O<sub>2</sub> at about 4000 kelvin. —] 21:18, 10 November 2006 (UTC)

Of course, ] is mostly water. :-) ] 21:45, 10 November 2006 (UTC)
:...with dissolved oxygen gas! Though as far as hotness...um, I didn't make the cut for the Under The Labcoat 2007 calendar. ] 22:03, 10 November 2006 (UTC)

== Things to be discover ==

What do you think are the next more important discoveries to be done?
I suggest: cure for AIDS, cheap clean energy, cheap space travel, light computation??] 22:32, 10 November 2006 (UTC)

:I picture programmable hunter-killer viruses. For example, a patient's cancer cell can be extracted, then a hunter-killer virus is programmed to destroy any cell with that exact DNA sequence. It's placed back into the body of the patient, and infects and destroys any cells with that DNA. After all the cancer cells are dead, the virus loses the ability to reproduce, and dies off, too. ] 22:37, 10 November 2006 (UTC)

::I like StuRat's idea, but it would be great for conservation. Something like that which could destroy ], and save many frog populations of the world. But, something needs to be done about climate change, or it would be all useless. --] 23:12, 10 November 2006 (UTC)

:::When StuRat mentioned programmable hunter-killer viruses, I thought of a computer virus that targets spammers... ] 23:40, 10 November 2006 (UTC)

:::::Oh, yes, please! ] 20:42, 11 November 2006 (UTC)

::::Viruses are one way to change DNA for gene therapy, but the problem is they are unpredictable, cannot be retracted, and are capable of mutation. Right now, it seems like RNAi is the future of gene manipulation. And you'd never believe where it comes from: worms. If you ask me, what scientist need to do next is to determine the exact etiology of disease (pick one...). If we know what goes wrong in the human body, ''precisely'', only then can we hope to fix it. ] 23:48, 10 November 2006 (UTC)

:::::] doesn't come from worms... RNAi was first observed in plants (although it wasn't called RNAi then) and was then (and is now) used rather successfully for gene knockdowns with ] (and is also used for gene silencing in transgenic plants). However we're simply taking advantage of a existing (still poorly understood) mechanism for gene regulation that occurs throughout the eukaryotes. ] 15:35, 11 November 2006 (UTC)

:::hunter-killer viruses would be a scary invention considering viruses pnchant for mutation. rechargeable battery technology for cars and other mobile appliances would transform the world. Stored energy with high enough density to enable flight and cars without burning fuel or toxic byproducts (or toxic accidents) would change everything. Climate Change is social problem, not a scientific one, meaning that current environmental goals of political organizaitons such as the UN and other states are geared towards wealth redistribution, not science. Climate change is a function of being on the planet. --] 05:55, 11 November 2006 (UTC)

:I don't know why cheap space travel is so important. A cure for AIDS is but there are also a lot of other medical related issues which are major problems in developing countries. Malaria, TB and cholera are three that come to mind. Some would argue these don't require inventions others would say they do. ] 15:35, 11 November 2006 (UTC)

:Understanding ] would be big, but probably nowhere near 'next'. When Einstein was asked what he would want to ask God, he said "Why turbulence?" (or something thereabouts). ] 20:42, 11 November 2006 (UTC)

:Tbeatty, you say "Climate change is a function of being on the planet". Do you mean by that that it is an inevitable natural occurrence (which is true) or that human induced 'Climate change on steroids' is inevitable (which isn't true)? ] 20:42, 11 November 2006 (UTC)

::The planet's climate change is an inevitable natural occurance. Natural variations far exceed any predictions about the human contribution. --] 21:04, 11 November 2006 (UTC)

=="impossible Physics"==

Can someone begin a "list" of the "impossible Physics" that our astronomers witness within visual space. Im interested in things that physically are "suppossed" to be impossible based off certain standards scientists have created throughout human history.

eg.. Black Holes, timing issues, etc...

Thanks
] 00:05, 11 November 2006 (UTC)

*Sending information faster than the speed on light via ]. ] 02:28, 11 November 2006 (UTC)

:*I don't think they've observed this, have they?--] 02:45, 11 November 2006 (UTC)

::*I believe that they have sent an audio transmission faster than the speed of light. ] 08:29, 11 November 2006 (UTC)

:::* I would like to see this. The only thing that I have seen that is faster than light is phase information. This isn't real information and can't be used to transfer real information. The other thing is coupled photons (I forget the real name). They are coupled and their existence is actually known before they are created but I think they still obey speed limit rules.--] 08:50, 11 November 2006 (UTC)

::::*Here is the article: and here is the relevant excerpt:

::::::''Professor Gunter Nimitz of Cologne claims he has transmitted Mozart across a 14 cm metal barrier at 4.7 times the speed of light. Professor Raymond Chiao of California has also measured transmission at 1.7 times the speed of light. This was reported in the BBC science program "Horizon". According to Einstein, faster than light travel is not possible, if one starts at below light speed; so these results are astounding. They rely on a mechanism called quantum tunneling, where a photon can be in several places at once. Some believe that the photon is really interacting with another one in a parallel universe, hence the weird effects seen when, for example, two photons sent through two separate slits, instead of forming two distinct bright spots, interact with each other, producing many dark and light bands. How one photon can be in so many places at once is for budding geniuses to explain.''

:::::] 09:02, 11 November 2006 (UTC)

::: To clarify this. Prof. Nimtz is considered an annoyance by many of his collegues due to his insistance on this claim. The facts, as the majority of physicists in the field see them, are as follows: There is a well known ] in ] with respect to the phenomenon of ]. The description of tunneling by means of the ] says that the time that a particle needs to tunnel through the barrier is independent of the length of the tunnel, and hence, a particle that travels through a very long "tunnel" appears to be travelling ] if you take the solution at face value. Nimitz set out to demonstrate this in the lab using the simplest possible realization of quantum tunneling: ]s propagating through a ] (simply a conducting, hollow metal tube; here with square cross section and a few dozens of centimeter long) which is too small to conduct the waves (i.e. the width is (slightly) less then half the wave length). Then, ] ] say the the wave is ]ly ], i.e. only a tiny bit comes out at the other end. The tunneling solution also says that the wave comes out "too early". But how do you measure the time that the wave needs to traverse the waveguide? A wave is not point-like, but has some extension. Nimitz, it seems, looked at the "center of mass" of the wave packet, which indeed moves faster than light. However, the information that the ] carries, enters the wave guide already as soon as the leading flank, i.e. the first bit of the wave enters, and the it should be considered as arrived once the leading flank exits. Careful theoretical analysis of the solution of the Schrödinger equation shows that the leading flank, other than the "center of mass", does not travel faster than light, i.e. ] and hence ] is not violated. As far as I am aware, Nimtz agrues a minority position by claiming that his experiments are not covered by this theoretical analysis. ] 10:59, 11 November 2006 (UTC)

::: I've just looked at Google scholar: I was unjust to Nimtz by making him appear stubborn. It seems that in his more recent publications, Nimtz now embraces the claim that "faster-than-light effects" in tunneling cannot violate causality. The debate is hence now no longer whether special relativity and its light-speed barrier is challenged by tunneling experiments (it is not), but rather how to correctly explain why it is not and whether it is proper to call it "faster-than-light" nevertheless. ] 11:56, 11 November 2006 (UTC)

Is this intended to be ammo for a ID vs. Evolution debate? ;) - ] ] (, ) 03:33, 11 November 2006 (UTC)

= November 11 =

== Paper Mache ==

What is an easy way to create paper mache using newspaper and masking tape? I can't seem to find any methods on Google. The final product will be used to support weight. (It is a chair. The base can only be 200 square centimeters touching the floor.) --] 02:59, 11 November 2006 (UTC)

:You can certainly tape a lot of newspaper together to support weight, but that is not what ] is at all. ] 02:22, 11 November 2006 (UTC)


::You don't need tape to create paper mache. Just get a bowl and fill it with glue. Rip up strips of newspaper, and throw them in the bowl. Then, paste these strips of newspaper onto whatever surface you want them on. --] 02:33, 11 November 2006 (UTC)

:Perhaps I should make my question clearer. I want to make a paper mache like substance only using newspaper and masking tape. (kind of like liquefied masking tape) How can that be done? I cannot use glue. Maybe paper mache is not the correct word to use. How would I go about compressing newspaper then taping it efficiently? Sorry if my question was vague, because I am asking this question on behalf of my sister. Thank you. --] 03:02, 11 November 2006 (UTC)
::You could shred and wet the newspaper and compress it into the forms you want, then once they're good and dry you could wrap them in masking tape to fasten them together and help them keep their shape. ] 03:41, 11 November 2006 (UTC)
::: What is wrong with glue? Note that you are not supposed to use the kind of glue that children or hobbyist use to glue paper together. this stuff is to sticky and dries to fast: you cannot model. For paper maché, you use the old-fashioned kind of glue which one uses to affix wallpaper to walls. It's a dilute liquid stuff which sticks only mildly to your hand, so that you can easily mix a bowl with this glue with paper shreds and start sculpting. (If my dictionary is right, English really lacks proper terms to describe the different traditional kinds of glue, such as the kind of glue, we are talking about here, and which is called ] in German. The German wikipedia article says it is a mixture of water and either ] or ]. Usually, you buy it in DIY stores as a powder and mix it with water.) See also ]. ] 11:13, 11 November 2006 (UTC)
:::: From memory, you can make it by cooking ] with water. Other flours would probably work as well. Also, I used to call it something and not glue. Possibly gum glue or gum paste or something. You could buy it in a small tub (already made) in Malaysia and this stuff tended to work better (I think) and last longer then homemade stuff (not sure whether it was that different or just had presevatives of some kind). This page may be interesting ] 15:02, 11 November 2006 (UTC)

== Kepler ==

What is the title of the book that has a clear discription of Kepler's discovery that spherical balls do not fall straight down from the edge of a table? The chapter's discussion points out how Kepler put ink on the balls to determine trajectory distances on a piece of paper he laid out on the floor. The discussion goes on to point out that the notion of trajectory made him ask the question, "what if the ball's trajectory flew past the edge of the earth?" ] 02:38, 11 November 2006 (UTC)

== A question on the biology of free will. ==

If the brain is a chemical machine, and all physical objects -- including neurons -- adhere to a system of laws, isn't it possible to predict the future behaviour of a person based on the billions of minute events occurring in the brain? Doesn't this imply that there is no such thing as free will? (I have very little education in psychology or neurology, this is merely something I'm curious about.) <small>—The preceding ] comment was added by ] (] • ]) 03:12, 11 November 2006 (UTC{{{3|}}})</small>
:Well, you've got some pretty big if's in there, depending on what you mean by "a system of laws". Modern physics, at least in some interpretations, is not completely deterministic -- see ]. However, even if quantum indeterminacy can show up at the neuronal level, behavior that's unpredictable merely because it's ''random'' is not what most metaphysical ] would consider to be "free will". For true free will, there does seem to need to be some non-physical part of the story, such as a soul. --] 03:35, 11 November 2006 (UTC)

:No, because so much of human behaviour consists of reactions to outside stimulii. It might be barely possible to predict a particular person's reaction to a particular event. ] 03:43, 11 November 2006 (UTC)

:You might as well ask if free will is an illusion cause by imperfect knowledge or ask how can you tell if reality is real - how do you know you aren't really a brain in a jar being fed artificial stimuli of a 'reality' totally different from your actual 'true' reality. You don't have a way of knowing, as there is no testable difference. ] 04:37, 11 November 2006 (UTC)

::We have a featured article on ], and it has sections on perspectives of various scientific disciplines on the subject. --] 04:41, 11 November 2006 (UTC)

If there is an apparently "random" element, some would suggest that this random element is directed by the "soul" of the individual, thus providing free will. ] 06:09, 11 November 2006 (UTC)

: Considering random, there is the ] level, and random events can and do happen there. Perhaps the soul lies in the ]? ] 06:16, 11 November 2006 (UTC)

:See the articles ] and ]. In thinking about this issue I have always found it an unsurmountable problem to give a working definition of "free will". However, whatever the definition, I don't get why people think that true quantum randomness can save a concept of "freeness" of the will under assault by determinism. &nbsp;--]] 20:44, 11 November 2006 (UTC)
::I don't think that's the claim. The point is not that quantum randomness constitutes freedom, but rather that, since the outcome of a quantum interaction is not determined, there is an opening for an agent-caused outcome without violating any physical laws. For a simple example, imagine a situation in which QM tells you that a neuron may fire, or not fire, with probability 1/2. The agent's choice causes it to fire. Looking at it from the outside, you can't establish that the agent has manipulated physical reality, because it might have fired anyway. --] 20:56, 11 November 2006 (UTC)

== Refractive index of cellulose ==

What is the ] of ]? ] 03:43, 11 November 2006 (UTC)
:You should try a google search. It depends on what exact cellulose polymer, cellulose is 1.5400; Cellulose nitrate is 1.5100; Methyl cellulose is 1.4970; Ethyl Cellulose is at 1.4790. ] 15:55, 11 November 2006 (UTC)

== Supernova ==

If there was a supernova at the centre of the Milky Way (which is obscured by dust in optical wavelengths), how bright would it appear? Let's say the ] turns into a supernova. Since all but a billionth of its light is blocked by dust, can we even see it without a telescope? --] 06:25, 11 November 2006 (UTC)

:Don't know about optical but ] would certainly see a neutrino shower. Maybe it would also trigger ]? -- ] 11:43, 11 November 2006 (UTC)

::Yes, you would be able to see it without a telescope

:::How bright (what magnitude) would it be? --] 20:24, 11 November 2006 (UTC)

::::It depends on the type of supernova. If it were a type 1a it would have a magnitude of about -19.6 (they all have very similar magnitudes). Type 2b supernovae vary quite a lot.

== Could science achieve this in the future? ==

As you probably know, your brain stores all the information, knowledge and memories you have acquired since birth.

In the future, would it be possible for scientists to dissect the brains of dead people to uncover the information, knowledge and memories the deceased have acquired during their lifetime?

There would be endless possibilities if this could be achieved. For example, if someone was murdered, scientists could dissect their brain and find the part which stores memories of their murder, and hence find out who was the murderer. If there was a fast food chain with a secret recipe very few people knew, and one who knew the recipe died, scientists could dissect their brain and find out the secret recipe.

:Yes, it's possible, some day, but the far more important value would be the ability to reproduce the mind of the dead person in a computer. ] 08:26, 11 November 2006 (UTC)

::If your mind can be recovered, are you really dead? I don't think memories from dead people will ever be recoverable, however it may be possible for live people to transfer memories electronically at some point. --] 08:41, 11 November 2006 (UTC)

:::I seriously hope it is and will remain science fiction. I also think it will never be possible, as the information in the brain is probably not stored as text and images but instead by complex connections and relations between personal experiences, memories, and emotions. –]<font color="#00aa00">]</font> 09:04, 11 November 2006 (UTC)

The brain is not a very well-understood organ. We know a lot about it, but there's also so much more about the human brain/mind that we do not know. Questions like this become almost a matter of personal philosophy. I for one, believe that everything you are is in the phyiscal brain, so that there is no spiritual 'mind', 'spirit' or 'soul' aside from what the brain generates. Therefore, i would say the answer to your question is yes. I believe with the rate biology is advancing, there will be a point in the future where we will have the ability to take a phyiscal brain, and in effect 'extract' everything the person whom the brain belonged to knew. To replicate all the connections of a biological brain with technology. I suppose, this ultimately means (for someone with my beliefs at least) that the person isn't really dead, because everything that made him/her who he/she is is in the brain. And then from there, speculation becomes fantasy.

A quote of interest here, which i remember but can't remember were from, went something like this "If our brain was simple enough for us to understand, then we would be too simple to understand it." Perhaps it's true we may never achieve that level of understanding regarding how our own minds work? And i would imagine, advances in technology allowing people to 'extract' knowledge from another person's brain would be highly contraversial, brining to life entire new ethical and moral issues. So i guess it really isn't something we can expect in the near future after all. --] 10:34, 11 November 2006 (UTC)

:*I disagree. No individual human may understand all the workings of a brain, but collectively, and with the aide of computers, we may. A much simpler device, like a car, is understood well enough by all of us collectively to construct, optimize, repair, and use it. However, few individuals likely understand every aspect of everything that happens to make a car operate. Your auto mechanic, for example, probably has no idea about the chemistry and physics behind combustion, he just knows what the proper air-fuel mix is to get the most power out of the engine. And the physicist who does understand all the theory may not know what the acceptable clearances are for the cylinder. ] 20:20, 11 November 2006 (UTC)

*To be honest I think the original contention ''"...your brain stores all the information, knowledge and memories you have acquired since birth"'' is highly unlikely, and certainly unproven. Thus further discussions are mere speculation. And even if there was some validity to the argument, tracing the neural pathways of specfic thoughts and memories would seem to be extremely difficult, if perhaps not necessarily impossible. I also suspect these would degenerate VERY quickly after death. --] 14:01, 11 November 2006 (UTC)

:*Decomposition would certainly destroy the memories stored in the brain, and freezing might, as well. But, that would give scientists a few days to work, perhaps enough time with some future technology. And embalming might preserve the memories indefinitely. ] 20:13, 11 November 2006 (UTC)

== The human liver and the break down of alcohol ==

How is it that the human liver is capable of breaking down so much alcohol? Where in human evolution did our liver become so effective? I don't see anthing that would cause prehistoric man to become specialzed such as having a high alcohol diet. ]. ] 07:24, 11 November 2006 (UTC)
:The article you provided says that the bacteria in the digestive tract produced alcohol which was toxic and needed to be broken down. Even the human liver can't stand a high alcohol diet and will suffer damage, or develop conditions such as ]. –]<font color="#00aa00">]</font> 08:15, 11 November 2006 (UTC)

:It brings up the question as to why is alcohol intoxicating? It seems that if alcohol were so debilitating, users of it would be selectively removed from the gene pool. I suspect that spoiled grain and fruit were staples of the early diet and that natural alcohols needed to be processed whence the development (or rather selection) of alcohol dehydrogenase. I don't think it was alcohol that was produced by bacteria in the digestive tract as that bacteria would still exist. Does that bacteria exist? Whose water do you have to drink to get it? --] 08:38, 11 November 2006 (UTC)

::You can look at nearly every non-inert small organic molecule, and it will be toxic in the quantities people fill themselves with. Most chemicals are poison, really. -- ] 11:48, 11 November 2006 (UTC)

::Why are you so sure humans have a unique ability to breakdown alcohol? Do you have any evidence for this? I suspect you will find chimpanzees and cats probably have similar abilities as ours. Bear in mind a fair number of ] have defects in ] affecting their ability to digest (and therefore consume) alcohol (see ]) ] 14:49, 11 November 2006 (UTC)

: The question is really good. Consider ] as a counterexample. AFAIK it is also naturally produced by bacterial decomposition, however, it is significantly more toxic than ethanol. A glass of 40% methanol will probably kill you, a glass of vodka will probably not (unless you drive, but that's a different story). Anyway, what is the biological significance of ethanol? Does it has a signal function of some sort like ], or is it just "serendipity" that ethanol doesn't kill us straight away, while methanol or, say, acetone do? I do not know. Anyone? --]
::] also breaks down ] and ] to a certian extent, and you do actually produce very small amounts of ] when your body is in a fasting state, see ], of course acetone is waste product, and it leaves your body the way most waste products do--] 19:55, 11 November 2006 (UTC)

== Hospital Information ==

Is there a free site where I can find information regarding surgical volumes for medical facilities?
:Are you talking globally? Nationwide? For some region? Over what period? ] 07:41, 11 November 2006 (UTC)

:What's a "surgical volume?" ] 08:29, 11 November 2006 (UTC)

::At a guess, I would think he mean's how many patients for all kinds of surgery there are (i.e. surgical throughput). However the question is in what area and over what period as anchroess said. ] 15:25, 11 November 2006 (UTC)

== Radial Tunnel Syndrome ==

I was diagnosed with Radial Tunnel Syndrome and all I was given was anti-inflammatories. I was not given or told to wear a brace or do any type of excercise. My next appointment is in 6 weeks. My two questions are: (1) should I be doing some type of treatment during these 6 weeks, such as wearing a brace. (2) What is the full recovery rate percentage, and if everything goes as planned (whether it's surgery or non-surgical treatment), will I be able to do serious heavy lifting again.
:The Reference Desk cannot give medical advice. However, by googling I found e.g. and which suggest avoiding rotating the wrist or bending the arm at the elbow. –]<font color="#00aa00">]</font> 11:47, 11 November 2006 (UTC)

== The little black hole that could ==

Suppose we created a microscopic black hole. Ignore ] and assume that the black hole's mass is exactly equal to the mass of material that has passed through its event horizon. We are going to place our black hole on the surface and watch it fall through the Earth's gravity well, eating matter as it goes. It will oscillate through the Earth, falling from one side to the other. Assume also that the earth is a rigid, uniformly dense sphere with infinite structural integrity, so it won't collapse in on itself - the only way to remove matter from the earth is to transfer it into the black hole, and that only happens to matter that crosses its event horizon.

Initially, the black hole has insignificant mass and will just pass through the earth. Over time, however, more of the earth's mass will be transferred into the black hole. What I'm actually interested in is, what would be the behaviour of this system under Newtonian mechanics? We have what is basically a point mass falling through a uniformly dense sphere, and the point's mass grows from zero to one in direct proportion with the sphere's mass shrinking from one to zero. How would the two bodies movements change as the black hole grows? Any other interesting thoughts about this idea are welcome. ] <small>(] | ])</small> 12:55, 11 November 2006 (UTC)

:You cant have little black holes, they have to be of such a mass that when the star that created them collapsed, they were crushed by their own gravity, into a singularity, which is my other point, all black holes are the same size, in that they have no size. They are singularitys. ] <sub>]</sub><sup>]</sup><sub>]</sub><sup>]</sup> 14:12, 11 November 2006 (UTC)

:Of course, you can have little black holes. Every star size BH will shrink to such a size, due to Hawking radiation. As to the original problem, it boils down to the same problem of a second mass in Earth's orbit if the BH is on an orbit that doesn't pass through the earth. If it passes through, deceleration because of side effects like a mini accretion disk and such will lead to it orbiting the mass centre of the Earth within the Earth, with crushing it finally when it has enough mass. -- ] 14:58, 11 November 2006 (UTC)

::Three points: Microscopic black holes are theoretically possible - and are believed to have existed in the early Universe. The current thinking on Hawking radiation is that it wouldn't actually cause black holes above a certain size to evaporate (the method by which Hawking radiation is generated means the black hole must absorb matter in direct proportion to the radiation they 'emit' (for want of a better word). The second point: Black holes are a feature of GR; there is no Newtonian treatment of black holes. Thirdly: Black holes do have a size. The event horizon of the black hole marks its boundary and has a radius dependent on the mass of the black hole (known as the Swartzchild radius)

:May we assume that the black hole is not rotating, and that – as the Earth in this problem has "infinite structural integrity" – the black hole eats out a hollow track with cross section πr<sup>2</sup>, where r is the ] of the black hole? &nbsp;--]] 19:46, 11 November 2006 (UTC)

Note that, as the black hole feeds, it's event horizon will expand. (Unlike us, however, it won't need to loosen it's belt.) :-) ] 20:06, 11 November 2006 (UTC)

== Hard skin ==

Is there a name for a lump of hard skin just below the surface. I have one and the doctors (including the orthopedic surgeons) dont know what to call it. --] 16:04, 11 November 2006 (UTC)
:You'll have to be more specific or else provide a picture. If it's a hard lump, it's important to know whether or not it feels like it is attached to the skin or moves separately from the skin. Dermatologic questions are really hard to answer over the internet. ] 18:33, 11 November 2006 (UTC)

It seems attached to the outer surface of the skin and can be moved about =/- 5mm horizontally in relation to the underlying flesh. Its a hard lump A bit like a ] but uner the surface. Surgeon says it might be a ] but wont know till he cuts it out. If its not serious (ie just hard skin) I may not want to have it cut out as it will leave a scar and prevent certain activites that I use my hand for.--] 18:49, 11 November 2006 (UTC)

:I think that last part was TMI. Are you sure it's not a swollen gland in the hand? --] 21:13, 11 November 2006 (UTC)

::I didnt know there were glands in the hands! Unless you mean .... 8-)
--] 21:32, 11 November 2006 (UTC)

== Laypersons ==

Why do laypersons think they understand many concepts that no physicists claim they understand? This is particularly prevalent with questions concerning black holes and some aspects of quantum mechanics. (This may apply to other sciences)

*Usually bad Cable Scifi/Cop/CSI shows, writters tend to throw around very bad science as technobabel--] 17:08, 11 November 2006 (UTC)

:Becuase theyre looking at it from a different point of view untrammelled by the 'facts'?--] 17:14, 11 November 2006 (UTC)
::Sort of like this whole page :)? --] 21:14, 11 November 2006 (UTC)

While the math requires a physicist, the interpretations do not. For example, the fact that certain "particles" follow a wave probability function doesn't immediately tell you what that says about them. The interpretation, however, is that they really aren't in any particular location, but only have a probability of being there. Also, whether they are passing in and out of parallel universes seems to be a matter of interpretation, depending on what one makes of ]. ] 19:48, 11 November 2006 (UTC)
*Exactly right, when people draw interpretations without actually understanding the underlying concepts, they usually wind up pulling interpetations out of their asymptotes. But popular mistakes usually take on a life of their own, and before you know it they become "]" For instance, the difference between a ']' and a ], or ']' and ].--] 20:10, 11 November 2006 (UTC)
:Hmmm Shouldnt those pages be 'dab'ed?--] 20:41, 11 November 2006 (UTC)
::] and ], one's a see also, the other is already disambiguated--] 20:44, 11 November 2006 (UTC)

:::<i>While the math requires a physicist, the interpretations do not.</i> This is exactly the point. The maths strongly resists interpretation into non-mathematical language. Added to that, the 'interpretations' are all drawn by physicists who already understand the maths and can very rarely be appreciated by people who don't understand the underlying maths. This is largely what leads to laypeople's mis-understanding of concepts.

== Determining molecular structure ==

How do you determine the structure of a molecule? ] 17:36, 11 November 2006 (UTC)

: Look ] -- ].

: ], ], ], just to name a few, depends on what the molecule is, and in what state your sample is in--] 19:40, 11 November 2006 (UTC)

== Why does nature likes so much to produce things in pairs? (two ears, two eyes, two lungs, two legs, four legs... ==

So why is it? Are intelligent creationists right?] 20:13, 11 November 2006 (UTC)

*See ], ], and ], also ] while you're at it --] 20:17, 11 November 2006 (UTC)

:Symmetry and redundancy. ] 20:19, 11 November 2006 (UTC)

:Symmetry. And Yould have difficulty walking with only one leg.--] 20:34, 11 November 2006 (UTC)
::If humans had only one foot they would probably have some other mechanism of moving. ("Intelligent creationists"? :-) –]<font color="#00aa00">]</font> 20:53, 11 November 2006 (UTC)

:::"intelligent creationist": someone who believes on "intelligent creation", also plainly known as creationist. It sounds logical isn't it?] 20:56, 11 November 2006 (UTC)

Latest revision as of 00:05, 25 December 2024

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December 10

Proton decay and cosmic expansion

A friend's physicist father opined that the phantom energy causing more and more rapid cosmic expansion will never be as strong as the attraction of the strong force, so protons will not be ripped apart in the big rip. Be that as it may, if the phantom energy is counter to the strong force, however weakly, wouldn't protons, consisting of quarks held together by the strong force, have an increased rate of decay in the far future? I have heard that the theories that protons do undergo decay at all have not yet been supported by experiments, though. Rich (talk) 13:41, 10 December 2024 (UTC)

We have to suppose quite a few things to get to the question: suppose there is some form of proton decay, suppose there is phantom energy, and suppose that the phantom energy reaches some plateau before getting to an energy scale high enough to create a quark-gluon plasma. Would protons then decay at a faster rate? I don't think that's necessarily the case. Proton decay is not the same kind of process as making a quark-gluon plasma. I believe the answer depends on what kinds of operators lead to the hypothetical proton decay. --Amble (talk) 22:49, 10 December 2024 (UTC)
Thanks, nice clarification of the issues. You've thought through the issues more clearly and knowledgeably than I did. That's a valuable answer. But having said that, is there more information available about current speculations and theoretical work by physicists concerning proton decay interacts with cosmic expansion? I can't be the only one wondering about it and many of the people wondering about it would be physicists.Rich (talk) 07:30, 13 December 2024 (UTC)
The nearest paper I came across is , but there "proton decay" actually means p → n + e + ν and not p → e + 2γ. --Amble (talk) 20:22, 13 December 2024 (UTC)

December 13

What is the most iconic tornado photo

Request for opinions
The following discussion has been closed. Please do not modify it.

What photo of a tornado would you say is the most iconic? I'm researching the history of tornado photography for an eventual article on it and I've seen several specific tornadoes pop up over and over again, particularly the Elie, Manitoba F5 and the "dead man walking" shot of the Jarrel, Texas F5. Which would be considered more iconic? ApteryxRainWing🐉 | Roar with me!!! | My contributions 17:21, 13 December 2024 (UTC)

At the top of this page is a bullet point stating "We don't answer requests for opinions, predictions or debate": this reads to me like a request for subjective opinions. Perhaps you would like to consider what quantifiable and referenceable metric would answer what you want to know?
Presumably you also want only real tornadoes considered? Otherwise some might nominate the the twister from The Wizard of Oz, or from more recent tornado-related movies – Sharknado, anyone? :-). {The poster formerly known as 87.81.230.195} 94.1.223.204 (talk) 18:07, 13 December 2024 (UTC)
"Swegle Studios" has a couple of YouTube videos dedicated to the backstories of famous tornado photos and video; you might find them useful in your research. Photos, Videos. Matt Deres (talk) 18:40, 13 December 2024 (UTC)
I googled "most iconic tornado photo" and a bunch of different possibilities popped up. I don't see how you could say that any given photo is the "most iconic". ←Baseball Bugs carrots18:57, 13 December 2024 (UTC)


December 15

help to identify File:Possible Polygala myrtifolia in New South Wales Australia.jpg

possible w:Polygala myrtifolia in New South Wales Australia

Did I get species right? Thanks. Gryllida (talk, e-mail) 06:56, 15 December 2024 (UTC)

related: https://species.wikimedia.org/Wikispecies:Village_Pump#help_to_identify_species Gryllida (talk, e-mail) 06:57, 15 December 2024 (UTC)
FWIW, I can't detect any visible differences between the plant in this photo and the ones illustrated in the species and the genus articles. However, the latter makes it clear that Polygala is a large genus, and is cultivated, with hybrids, so it's possible that this one could be a close relative that differs in ways not visible here, such as in the bark or roots. That may or may not matter for your purposes. {The poster formerly known as 87.81.230.195} 94.1.223.204 (talk) 10:11, 15 December 2024 (UTC)

How to address changes to taxonomy

Hi all, I am a biology student brand new to wiki editing who is interested in cleaning up small articles/stubs for less known taxa. One that I've encountered is a mushroom that occurs in the pacific northwest (Fomitopsis ochracea). The article mentions that this fungus is occasionally mistaken for another fungus, Fomitopsis pinicola.

However, the issue I've run into is that F. pinicola used to be considered a single species found around the world, but relatively recently was split into a few different species. The original name was given to the one that occurs in Europe, and the one in the pacific northwest (and thus could be mistaken for F. ochracea) was given the name Fomitopsis mounceae.

The wiki page says

Historically, this fungus has been misidentified as F. pinicola. When both species are immature, they can look very similar, but can be distinguished by lighting a match next to the surface of the fungus. F. pinicola will boil and melt in heat, while F. ochracea will not.


Since the source says pinicola (as likely do most/all other sources of this info given the change was so recent), and since technically it's true that they used to be mistaken for it... what would be the most appropriate way to modernize that section?

My questions are: Should I replace F. pinicola with F. mounceae? Or is that wrong because the source doesn't refer to it by that name? Would it be better to write something like (now known as/considered F. mounceae) next to the first mention of the species? Or is that a poor choice because it implies all the members of F. pinicola were renamed F. mounceae?

Any advice on how to go about updating this section is incredibly appreciated
TheCoccomycesGang (talk) 10:21, 15 December 2024 (UTC)

First, take these sorts of questions to the relevant Wikiproject, in this case Misplaced Pages talk:WikiProject Fungi. I am not as familiar with the consensus at WP:FUNGI, but it seems like they defer to Species Fungorium/Index Fungorium and Mycobank to decide. Those sources presently seem to consider Fomitopsis pinicola a good species. Also, be careful about "replacing", there are rules to ensure the continuity of the article history. By the way, there is a hilarious but unencyclopedic/copyvio recipe appended to the Fomitopsis mounceae article. Abductive (reasoning) 11:09, 15 December 2024 (UTC)
Thanks for the tips, I didn't know about projects so I'll go read up on that. And thanks for the warnings about replacing things. I've been reading a lot of help pages, but I'm still in the process of learning the all conventions and what mechanics break if you do things the wrong way.
I actually saw the recipe ages ago before I made my account and completely forgot about it... it was one of many things that prompted me to get into wiki editing. TheCoccomycesGang (talk) 23:12, 15 December 2024 (UTC)

Does stopping masturbation lead to sperm DNA damage?

I'm looking for information on the potential link between the frequency of ejaculation (specifically through masturbation) and sperm DNA damage. I've come across some conflicting information and would appreciate it if someone could point me towards reliable scientific studies or reviews that address this topic.

Specifically, I'm interested in whether prolonged periods of abstinence from ejaculation might have any negative effects on sperm DNA integrity. Any insights or links to relevant research would be greatly appreciated. HarryOrange (talk) 17:08, 15 December 2024 (UTC)

Only males may abstain from sperm-releasing Masturbation that serves to flush the genital tract of old sperm that in any case will eventually dissipate. No causal relationship between masturbation and any form of mental or physical disorder has been found but abstinence may be thought or taught to increase the chance of wanted conception during subsequent intercourse. Philvoids (talk) 00:51, 16 December 2024 (UTC)
There's many rumors about that topic. One is that not ejaculating frequently increases the risk of developing prostate cancer. Abductive (reasoning) 01:02, 16 December 2024 (UTC)
Nothing really conclusive but there's some evidence that short periods are associated with lower DNA fragmentation, see
for example. Alpha3031 (tc) 02:12, 16 December 2024 (UTC)
Mature sperm cells do not have DNA repair capability. Inevitably, as sperm cells get older, they will naturally and unavoidably be subject to more and more DNA damage. Obviously, freshly produced spermatozoa will, on average, have less DNA damage. It is reasonable to assume that the expected amount of damage is proportional to the age of the cells, which is consistent with what studies appear to find. Also, obviously, the more the damage is to a spermatozoon fertilizing an oocyte, the larger the likelihood that the DNA repair in the resulting zygote, which does have DNA repair capability, will be incomplete. The studies I've looked at did not allow me to assess how much this is of practical significance.  --Lambiam 09:40, 16 December 2024 (UTC)

December 16

Abelian sandpile model

Thanks to those who answered my last question, I think it should be added to a disambiguation page. If anyone wants to help me write that, reach out.

A sandpile seems disorganized and inert, but these are critically self-organizing. Do the frequency and size of disturbances on sand dunes and snowy peaks follow power law distribution? Gongula Spring (talk) 01:18, 16 December 2024 (UTC)

Shouldn't this be at the Math Desk? Abductive (reasoning) 05:12, 16 December 2024 (UTC)
If the question is not about the model mentioned in the heading but about the physical properties of sand dunes and snowy peaks, this here is the right section of the Reference desk.  --Lambiam 08:51, 16 December 2024 (UTC)
I await a non-mathematical answer. Abductive (reasoning) 09:23, 16 December 2024 (UTC)
It depends is probably a fairly reasonable non-mathematical answer for these kinds of systems. For sand dunes anyway, sometimes avalanche frequency is irregular and the size distribution follows a power law, and sometimes it's close to periodic and the avalanches span the whole system. It seems there are multiple regimes, and these kinds of systems switch between them. Sean.hoyland (talk) 09:35, 16 December 2024 (UTC)
Thank you! I'm impressed this seems so casual, but surely you read this somewhere that might have a URL?
Gongula Spring (talk) 22:29, 19 December 2024 (UTC)
Hi, this is an interesting and somewhat open question! A lot of work is done on these models but much less on careful analyses of real dunes. I did find this dissertation that is freely accessible and describes some physical experiments and how well they fit various models. The general answer seems to be that the power law models are highly idealized, and determining the degree to which any real system's behavior is predicted by the model ahead of time is very difficult. Update: This is one of the earlier important works on the topic and it does include discussion of how well the model fits experiments.SemanticMantis (talk) 17:21, 16 December 2024 (UTC)
That dissertation is great!
Gongula Spring (talk) 22:30, 19 December 2024 (UTC)

Polar night

Are there any common or scientific names for types of polar night? The types that I use are:

  • polar night - meaning a day when sun's altitude remains below horizon entire day (there is no daylight at solar noon, only civil twilight), occurring poleward from 67°24′ north or south
  • civil polar night - meaning a day when sun's altitude remains below -6° entire day (there is no civil twilight at solar noon, only nautical twilight), occurring poleward from 72°34′ north or south
  • nautical polar night - meaning a day when sun's altitude remains below -12° entire day (there is no nautical twilight at solar noon, only astronomical twilight), occurring poleward from 78°34′ north or south
  • astronomical polar night - meaning a day when sun's altitude remains below -18° entire day (there is no astronomical twilight at solar noon, only night), occurring poleward from 84°34′ north or south

These names were changed on Polar night article, and I wnat to know whether these named I listed are in use in any scientific papers, or in common language. (And I posted that question here and not in language desk because I think that this is not related to language very tightly.) --40bus (talk) 18:56, 16 December 2024 (UTC)

Some definitions at The Polar Night (1996) from the Aurora Research Institute. Alansplodge (talk) 22:55, 16 December 2024 (UTC)
These seem to be generalizable as: X polar night is a period, lasting not less than 24 hours, during which the sun remains below the horizon and there is no X twilight. The specific definitions depend then on the specific definitions of civil/nautical/astronomical twilight. These can be defined with a subjective observational standard or with an (originally experimentally determined) objective standard.  --Lambiam 10:36, 17 December 2024 (UTC)
FWIW, I as a former amateur astronomer have never previously thought about the question of Polar twilight and night nomenclatures, but immediately and completely understood what the (previously unencountered) terms used in the query must mean without having to read the attached descriptions. {The poster formerly known as 87.81.230.195} 94.1.223.204 (talk) 16:34, 17 December 2024 (UTC)

December 17

differential equations with complex coefficients

In an intro ODE class one basically studies the equation x ˙ = A x {\displaystyle {\dot {x}}=Ax} where x is a real vector and A is a real matrix. A typically has complex eigenvalues, giving a periodic or oscillating solution to the equation. That is very important in physics, which has various sorts of harmonic oscillators everywhere. If A and x are complex instead of real, mathematically the ODE theory works out about the same way. I don't know what happens with PDE's since I haven't really studied them.

My question is whether the complex case is important in physics the way the real case is. Can one arrive at it through straightforward coordinate transformations? Do the complex eigenvalues "output" from one equation find their way into the "input" of some other equation? Does the distance metric matter? I.e. in math and old-fashioned physics we use the Euclidean metric, but in realtivity one uses the Minkowski metric, so I'm wondering if that leads to complex numbers. This is all motivated partly by wondering where all the complex numbers in quantum mechanics come from. Thanks. 2601:644:8581:75B0:0:0:0:DA2D (talk) 22:54, 17 December 2024 (UTC)

Perhaps I don't understand what you are getting at but simple harmonic motion is xdot=j*w*x where w is angular frequency and j is i Greglocock (talk) 00:35, 18 December 2024 (UTC)
If PDEs count, the Schrödinger equation and the Dirac equation are examples of differential equations in the complex domain. A linear differential equation of the form x ˙ = A x {\displaystyle {\dot {x}}=Ax} on the complex vector space C n {\displaystyle \mathbb {C} ^{n}} can be turned into one on the real vector space R 2 n {\displaystyle \mathbb {R} ^{2n}} . For a very simple example, using n = 1 , {\displaystyle n=1,} the equation [ z ˙ ] = [ i ] [ z ] {\displaystyle {\begin{bmatrix}{\dot {z}}\end{bmatrix}}={\begin{bmatrix}i\end{bmatrix}}{\begin{bmatrix}z\end{bmatrix}}} can be replaced by
[ x ˙ y ˙ ] = [ 0 1 1 0 ] [ x y ] . {\displaystyle {\begin{bmatrix}{\dot {x}}\\{\dot {y}}\end{bmatrix}}={\begin{bmatrix}0&-1\\1&0\end{bmatrix}}{\begin{bmatrix}x\\y\end{bmatrix}}.}
 --Lambiam 01:11, 18 December 2024 (UTC)
Shouldn't this be at the Math Desk? It almost seems like the IP could be trolling, given the same question just above. Abductive (reasoning) 14:49, 18 December 2024 (UTC)
The question whether the complex case is important in physics the way the real case is, is not a maths issue. IMO the Science section is the best choice. I do not see another post that asks the same or even a related question.  --Lambiam 21:51, 18 December 2024 (UTC)
Just as above, I await a non-mathematical answer to this question. Abductive (reasoning) 07:01, 19 December 2024 (UTC)

Thanks all. Greglocock, your SHO example is 1-dimensional but of course you can have a periodic oscillator (such as a planetary orbit) in any orientation in space, you can have damped or forced harmonic oscillators, etc. Those are all described by the same matrix equation. The periodic case means that the matrix eigenvalues are purely imaginary. The damped and forced cases are where there is a real part that is negative or positive respectively. Abductive, of course plenty of science questions (say about how to calculate an electron's trajectory using Maxwell's equations) will have mathematical answers, and the science desk is clearly still the right place for them, as they are things you would study in science class rather than math class. Lambiam, thanks, yes, PDE's are fine, and of course quantum mechanics uses complex PDE's. What I was hoping to see was a situation where you start out with real-valued DEs in some complicated system, and then through some coupling or something, you end up with complex-valued DEs due to real matrices having complex eigenvalues. Also I think the Minkowski metric can be treated like the Euclidean one where the time coordinate is imaginary. But I don't know how this really works, and Misplaced Pages's articles about such topics always make me first want to go learn more math (Lie algebras in this case). Maybe someday. 2601:644:8581:75B0:0:0:0:DA2D (talk) 07:25, 19 December 2024 (UTC)

December 18

Why don't all mast radiators have top hats?

Our mast radiator article describes a device called a "top hat" which increases the range for mast radiators that can't be built tall enough.

So, why would you bother building a mast radiator without a top hat? Couldn't you just build it shorter with the top hat, and save steel? Marnanel (talk) 15:00, 18 December 2024 (UTC)

The main source cited in our article states, "Top loading is less desirable than increased tower height but is useful where towers must be electrically short due to either extremely low carrier frequencies or to aeronautical limitations. Top loading increases the base resistance and lowers the capacitive base reactance, thus reducing the Q and improving the bandwidth of towers less than 90° high." If "reducing the Q" is an undesirable effect, this is a trade-off design issue in which height seems to be favoured if circumstances permit.  --Lambiam 21:41, 18 December 2024 (UTC)

Name of our solar system

Is our star system officially called "Sol", or is that just something that came from science fiction and then became ubiquitous? 146.90.140.99 (talk) 22:06, 18 December 2024 (UTC)

It's called the Solar System, and its star is called Sol, from Latin via French. Hence terms like "solstice", which means "sun stands still" in its apparent annual "sine wave" shaped path through the sky. ←Baseball Bugs carrots23:31, 18 December 2024 (UTC)
Via French? According to the OED, it came direct from Latin.  --Lambiam 11:45, 19 December 2024 (UTC)}}
Old French plus Latin.Baseball Bugs carrots14:25, 19 December 2024 (UTC)
Also in Old French, the word meaning "sun" was soleil.  --Lambiam 23:42, 19 December 2024 (UTC)
Let's say to that claim. The star is indeed called Sol if you're speaking Latin, but in English it's the Sun (or sun). Of course words like "solar" and "solstice" derive from the Latin name, but using "Sol" to mean "the Sun" does seem to be something from science fiction. --142.112.149.206 (talk) 06:04, 19 December 2024 (UTC)
"Sol" is occasionally used to mean the Sun by astronomers. I feel like it is used in contexts where it is necessary to distinguish our experience with the Sun here on Earth, such as sunsets, from more "sterile" aspects of the Sun one might experience off the Earth. Abductive (reasoning) 08:56, 19 December 2024 (UTC)
Being an astronomer myself, I don't think I've ever heard anyone use "Sol" outside of a science fiction context. --Wrongfilter (talk) 09:06, 19 December 2024 (UTC)
Scientific articles that use the term Sol; Development of the HeliosX mission analysis code for advanced ICF space propulsion and Swarming Proxima Centauri: Optical Communication Over Interstellar Distances. These are rather speculative but as I mentioned, the usage is for off-planet situations. Abductive (reasoning) 13:05, 19 December 2024 (UTC)
Using Sol, Terra and Luna to refer to the Sun, Earth and Moon only happens if you write your entire article in Latin and in science fiction, not in regular science articles. They are capitalised though. Just as people write about a galaxy (one of many) or the Galaxy (the Milky Way Galaxy, that's our galaxy). The Solar System is also capitalised. PiusImpavidus (talk) 10:38, 19 December 2024 (UTC)
The article says "Sol" is the "personification" of the sun. Google Image the term "old Sol" and you'll see plenty of images of the sun with a face, not just Sci-Fi stuff. And "Luna" is obviously the basis for a number of words not connected with Sci-Fi. Lunar orbit, lunar module, etc. And the term "terra firma" has often been used in everyday usage. ←Baseball Bugs carrots11:34, 19 December 2024 (UTC)
And yet, if you ask 1,000 people "What's that big yellow thing up in the sky called?", you'll get 1,000 "the Sun"s and zero "Sol"s. Yes, in specialised contexts, Sol is used; but that doesn't justify saying our solar system's star "is called Sol" without any qualification, as if that were the normal, default term. It's not. -- Jack of Oz 12:16, 19 December 2024 (UTC)
And after you've gotten that response, ask them why it isn't the "Sunner System". And why a sun room attached to a house isn't called a "sunarium". And why those energy-gathering plates on some roofs are not called "sunner panels". ←Baseball Bugs carrots14:22, 19 December 2024 (UTC)
What does that have to do with anything? The question was 'Is our star system officially called "Sol"?' (my emphasis). The answer is it is not. And that does not preclude other terms being derived from Latin sol (or, often enough, from Greek helios), nobody denies that, it is irrelevant to the question. --Wrongfilter (talk) 14:52, 19 December 2024 (UTC)
The problem is that the OP's question contains false premises. One is the question of what the "official" name is. There is no "official" name. It's the "conventional" name. And the second part, claiming that "Sol" comes from Sci-fi, is demonstrably false. ←Baseball Bugs carrots15:05, 19 December 2024 (UTC)
Then demonstrate (that the usage of "Sol" as a name for the Sun, in English, not its use to derive adjectives, originated outside of SF), with references. The original question does not even include any premises, with maybe the exception of "ubiquitous". --Wrongfilter (talk) 15:18, 19 December 2024 (UTC)
"Is our star system officially called "Sol" , or is that just something that came from science fiction and then became ubiquitous? ". And the wording of your own question, just above, does not make sense. ←Baseball Bugs carrots15:24, 19 December 2024 (UTC)
Looking at Newspapers.com (pay site), I'm seeing colloquial references to "old Sol" (meaning the sun) as far back as the 1820s. No hint of sci-fi derivation. ←Baseball Bugs carrots15:32, 19 December 2024 (UTC)
Great! Well done. --Wrongfilter (talk) 15:41, 19 December 2024 (UTC)
Feel free to box up this section. ←Baseball Bugs carrots15:52, 19 December 2024 (UTC)
The 1933 OED entry for Sol, linked to above, gives several pre-SF uses, the earliest from 1450.  --Lambiam 23:48, 19 December 2024 (UTC)
Yes, of course, but that's not surprising, is it? 15th century humanists, astrologers and pre-Victorian poets liked to sprinkle their texts with Latin words. But I don't think this is what the question is about. It's a matter of context, but it should be up to OP to clarify that. --Wrongfilter (talk) 08:48, 20 December 2024 (UTC)
It's not surprising, but the discussion was not whether the use of Sol in English texts is surprising, but whether it originated outside of SF.  --Lambiam 10:52, 20 December 2024 (UTC)
In my view, the question has a clear scifi bent, and that particular usage ("Where shall we go for our vacation? Alpha Centauri or Sol?") does not originate in the 15th century. The word is much older, of course it is, but the usage is not. In the 15th century people didn't even know that the Sun is just an ordinary star and could do with a particular name to distinguish it from the others. The connotations of sol were vastly different from what they are today and from what is implied in OP's question. Incidentally, the IAU doesn't even define a name , although they recommend using capitalised "Sun". Certainly no "Sol" anywhere. --Wrongfilter (talk) 12:04, 20 December 2024 (UTC)
Does that make it a Sol-ecism? Clarityfiend (talk) 12:19, 19 December 2024 (UTC)
More like a Sol-ips-ism. Meaning a factory where suns are made. From Sol = sun, and ipso = facto. Thus endeth the entymogology lesson for today. Go in peace to love and serve whomsoever. -- Jack of Oz 19:37, 19 December 2024 (UTC)

Mountains

Why there are no mountains on Earth with a height above 10,000 m? As the death zone is about at 8,000 m, and above 19,000 m, there is an Armstrong limit, where water boils at normal human body temperature, it is good that there are no more mountains higher than 8,000 km than just 14, but if there were hundreds of mountains above 9,000 m, then these were bad to climb. If there were different limits for death zone and Armstrong limit, would then there be possible to have higher mountains? I have just thought that, it is not a homework? --40bus (talk) 22:29, 18 December 2024 (UTC)

There are mountains elsewhere in the solar system that are over 20km high. Given that some of those are on airless worlds, I don't think the air pressure has any bearing on it. 146.90.140.99 (talk) 22:57, 18 December 2024 (UTC)
Multiple sources from web searching suggest the theoretical maximum height for mountains on Earth is around 15,000 m – the limiting factor is Isostasy; the higher (therefore more voluminous) a mountain is, the more its weight causes the crust beneath it to sink. The actual heights of mountains are a trade-off between how fast tectonic movements can raise them versus isostatic sinking and how quickly they are eroded, and tectonic movements do not last for ever. See also Orogeny. {The poster formerly known as 87.81.230.195} 94.1.223.204 (talk) 00:25, 19 December 2024 (UTC)
And erosion goes faster as the mountain gets higher, in particular when it's high enough to support glaciers – one reason why mountains can get higher on an airless world. Now it gets interesting for a mountain high enough to reach into the stratosphere, as it would be too dry to have anything but bare rock. I suppose it would locally raise the tropopause, preventing that. PiusImpavidus (talk) 11:13, 19 December 2024 (UTC)

December 19

Does human DNA become weaker with each generation?

As with photocopying something over and over, the text becomes less clear each time.

Does human DNA become weaker with each generation? HarryOrange (talk) 21:22, 19 December 2024 (UTC)

Sure, DNA replication is not perfect, although proofreading reduces the error rate to about 1 mistake per 10 nucleotides (see our article on DNA Replication). But that is per generation of cells, not of the whole organisms. Many mutations will be neutral in effect (because much of our DNA is redundant), some will be deleterious, and a few might be advantageous. It is the process of natural selection that hinders the spread of deleterious mutations: sometimes this aspect is called purifying selection. One thus usually expects a stable mutation–selection balance over time rather than that "DNA becomes weaker with each generation". Medical science is reducing the selection pressure against some mutations, which consequently may become more common. One of the problems for asexual organisms is referred to as Muller's ratchet; assuming that reverse mutations are rare, each generation has at least the mutational load of its predecessor. In contrast, in sexual organisms genetic recombination generates the variation that, combined with selection, can repair the situation. Sexual organisms consequently have a lighter genetic load. JMCHutchinson (talk) 22:42, 19 December 2024 (UTC)
So purifying selection won't work properly in case of Inbreeding ? HarryOrange (talk) 23:16, 19 December 2024 (UTC)
The larger the degree of inbreeding, the larger the chance that deleterious traits are expressed. But this very expression of traits leading to decreased biological fitness of their bearers is what actually enables purifying selection in the longer term.  --Lambiam 23:36, 19 December 2024 (UTC)
@Lambiam so DNA repair won't stop these deleterious traits to get expressed? HarryOrange (talk) 14:11, 20 December 2024 (UTC)
No, this is not an issue of damage to the DNA. The genes involved are faithfully reproduced and passed on from generation to generation.  --Lambiam 15:53, 20 December 2024 (UTC)
Or stronger e.g. "...we found that genes specifically duplicated in the Greenland shark form a functionally connected network enriched for DNA repair function", and those guys live for centuries and have much more DNA than us. Sean.hoyland (talk) 15:21, 20 December 2024 (UTC)
@Lambiam If not due to DNA damage, why do babies from inbreeding appear like DNA-damaged species? HarryOrange (talk) 17:29, 20 December 2024 (UTC)
Inbred offspring of species that normally outcross may show abnormalities because they are more likely than outcrossed offspring to be homozygous for recessive alleles that are deleterious. In individuals that are heterozygous at these loci, the recessive alleles will not be expressed (because the other wild-type dominant allele is sufficient to do their job adequately). See our article on inbreeding depression. JMCHutchinson (talk) 19:26, 20 December 2024 (UTC)

Larvae going south

In a novel I've just finished (The Chemistry of Death by Simon Beckett) he writes:

  • leave the body in an orderly fashion, following each other in a neat procession that always heads south. South-east or south-west sometimes, but never north. No-one knows why.

The author has done considerable international research on the science of forensic identification of decayed bodies and I assume his details can be trusted.

I've looked online for any verification of this surprising statement, but found only this, which seems to debunk it.

Is there any truth to this? -- Jack of Oz 23:38, 19 December 2024 (UTC)

Can't speak to its truth, but . . .
  • Does Beckett state this in his own auctorial voice (i.e. as an omniscient narrator)? If so, he might be genuinely mistaken.
  • The book was published nearly 20 years ago, what was the accepted wisdom then?
  • What specific species (if any) is the book describing? – your linked Quora discussion refers only to "maggots" (which can be of numerous species and are a kind of larva, but there are many others, including for example Processionary caterpillars).
  • Alternatively, if the statement is made by a character in the book, is that character meant to be infallible, or is he portrayed as less than omniscient, or an 'unreliable narrator'?
Regarding the statement, in the Northern hemisphere the arc of South-east to South-west is predominently where the Sun is found well above the horizon, the North never, so the larvae involved might simply be seeking maximum warmth or light. {The poster formerly known as 87.81.230.195} 94.1.223.204 (talk) 02:18, 20 December 2024 (UTC)
This appears in the very first paragraph of Chapter I, which starts out:
  • A human body starts to decompose four minutes after death. Once the encapsulation of life, it now undergoes its final metamorphoses. It begins to digest itself. Cells dissolve from the inside out. Tissue turns to liquid, then to gas. No longer animate, the body becomes an immovable feast for other organisms. Bacteria first, then insects. Flies. Eggs are laid, then hatched. The larvae feed on the nutrient-rich broth, and then migrate. They leave the body in an orderly fashion ... (then the quote above completes the paragraph).
It's not until para 2 that he starts talking about any human characters, and not until para 4 that he invokes the first person.
That's as much as I know. But I find it hard to believe he'd just make up a detail and put it in such a prominent place if it could so easily be debunked if it were not true. -- Jack of Oz 02:39, 20 December 2024 (UTC)
I wonder how they would measure the migratory path of maggots within a sealed coffin. ←Baseball Bugs carrots02:51, 20 December 2024 (UTC)
The context of the novel is about finding decaying corpses that have been dumped in a forest. No coffins involved. -- Jack of Oz 06:08, 20 December 2024 (UTC)
Baseball Bugs, see also body farm research facilities. Alansplodge (talk) 13:44, 20 December 2024 (UTC)
Could it be that the larvae are setting off in search of another corpse? The prevailing wind in the UK is from the south-west, so by heading into the wind they won't be distracted by the frangrance of the one they've just left. Shantavira| 09:30, 20 December 2024 (UTC)

If you can, have a look at 'Heinrich, Bernd. “Coordinated Mass Movements of Blow Fly Larvae (Diptera: Calliphoridae).” Northeastern Naturalist, vol. 20, no. 4, 2013, pp. N23–27. JSTOR, http://www.jstor.org/stable/43288173.' Here are some extracts

  • On the fourth day, after a cooling night with dew on the grass, a stream of tens of thousands of larvae exited from beneath the carcass within 1 h after sunrise, and proceeded in a single 1-2-cm-wide column directly toward the rising sun...
  • However, in this case, the larvae left at night, within 1 h after a cloudburst (at 21 :00 hours). But, unlike before, this nocturnal larval exodus in the rain was diffuse; thousands of larvae spread out in virtually all directions over an 8 m2area. Apparently, the sudden moisture had cued and facilitated the mass exodus, but the absence of sun had prevented a unidirectional, en masse movement.
  • However, on the following morning as the sun was starting to illuminate the carcass on the dewy grass, masses of larvae gathered at the east end of the carcass at 07:00 hours. In one half hour later, they started streaming in a column directly (within one degree) toward the rising sun, and the carcass was then nearly vacated.

It goes on. Maggot migration appears to be a bit more complicated than the novel suggests. Sean.hoyland (talk) 09:39, 20 December 2024 (UTC) I suppose you could try to address it from the other direction and look at the technology your average maggot has access to in terms of light detection, heat detection, olfactory systems, orientation in magnetic fields (like many arthropods) etc. They presumably have quite a lot of tools. Sean.hoyland (talk) 10:13, 20 December 2024 (UTC)

If orderly migrating maggots tend to move towards the sun, they should display a northward tendency in Oztralia.  --Lambiam 10:31, 20 December 2024 (UTC)
Maybe, but the novel is set in England.
I must say, as soon as I read the quoted para for the first time, my immediate thought was that it might have something to do with the magnetic field of the earth. -- Jack of Oz 10:42, 20 December 2024 (UTC)
Prime suspect might be the Bolwig organ, the photoreceptor cluster many fly larvae have. Sean.hoyland (talk) 10:49, 20 December 2024 (UTC)
Obviously, Jack, you need to create a corpse, place it in a nearby forest, and carefully observe which way the maggots go. For Science! And Literary Criticism! {The poster formerly known as 87.81.230.195} 94.1.223.204 (talk) 21:01, 20 December 2024 (UTC)

December 20

Winter solstice and time of sunrise?

How is it that despite December 21st supposedly being the shortest day of the year, sunrise here happens later and later until December 26 and only on January 05 starts to turn around to occur earlier and earlier. On December 25 it takes place at about 08:44, between December 26 and January 04 it takes place at about 08:45, and on January 05 it takes place again at about 08:44. (Google rounds out the seconds). Is it Google's fault? Is it everywhere the same? Confused in Brussels, Belgium. 178.51.16.158 (talk) 12:06, 20 December 2024 (UTC)

The pertinent article is Analemma, start with the section Earliest and latest sunrise and sunset. The details are not that simple to understand, but it's basically due to the ellipticity of Earth's orbit and its axial tilt. --Wrongfilter (talk) 12:22, 20 December 2024 (UTC)
Also note that sunset begins to be later on 22 December so that the time between sunrise and sunset is a few seconds longer than on 21 December (3 seconds longer on 22/12/24 in Brussels according to this). Alansplodge (talk) 13:33, 20 December 2024 (UTC)
Also see Equation of time#Major components. The obliquity of the ecliptic (that is, the Earth's axial tilt) is the main component and hardest to understand. But the idea is that the time when the Sun is exactly south (that is, the true noon) moves some minutes back and forth throughout the year and it moves quite rapidly to later times in late December. PiusImpavidus (talk) 19:05, 20 December 2024 (UTC)

Three unit questions

  1. Why territorial waters are defined by nautical miles instead of kilometers?
  2. Why GDP is usually measured in US dollars rather than euros? Euro would be better because it is not tied into any country.
  3. Are there any laws in United States that are defined by metric units?

--40bus (talk) 23:30, 20 December 2024 (UTC)

  1. There were nautical miles in use before there were kilometers.
  2. There were US dollars in use before there were Euros.
  3. Yes.
The questions all reduce to Why can't millions of people make a change of historically widely accepted units that continue to serve their purpose, and convert to different units that would have no substantive difference, because someone has an opinion. Philvoids (talk) 00:52, 21 December 2024 (UTC)
Do any people use metric units in marine and air navigation like "The ship is 10 kilometers from the port", "The plane is 10 kilometers from the destination? And is there any European country with metric flight levels? --40bus (talk) 07:22, 21 December 2024 (UTC)
Inland shipping (rivers, canals and lakes) in Europe (except the UK) is fully metric. Ships going for example TilburyDuisburg may have to switch units along the way. Gliders and ultralight aircraft in Europe often use metric instruments and airport dimensions are also metric (including runway length). Countries are free to define their territorial waters in whatever way they deem fit, so with nautical miles having no legal status in a fully metric country, they may define their territorial waters as extending 22224 metres. PiusImpavidus (talk) 11:23, 21 December 2024 (UTC)
Our nautical mile article says: "In 1929 the international nautical mile was defined by the First International Extraordinary Hydrographic Conference in Monaco as exactly 1,852 metres (which is 6,076.12 ft). The United States did not adopt the international nautical mile until 1954. Britain adopted it in 1970..."
As the US customary units are actually defined in terms that relate them to metric units, any US law based on measurements is technically defined by metric units.--User:Khajidha (talk) (contributions) 01:55, 21 December 2024 (UTC)
The US dollar has been the world's dominant reserve currency for about 75 years. As for the metric system in the US, it is standard in scientific, medical, electronics, auto manufacturing and other highly technical industries. By law, all packaged foods and beverages have metric quantities as well as customary quantities. See Metrication in the United States. Cullen328 (talk) 02:28, 21 December 2024 (UTC)

The Wikipaedia article on the Nautical Mile talks about how the term originated, it was originally defined in terms of latitude not as a number of meters 114.75.48.128 (talk) 10:03, 24 December 2024 (UTC)

December 24

Unknown species of insect

Am I correct in inferring that this guy is an oriental beetle? I was off-put by the green head at first, but the antennae seem to match. JayCubby 03:00, 24 December 2024 (UTC)

(reference: https://www.genesdigest.com/macro/image.php?imageid=168&apage=0&ipage=1)

It looks like one of the invasive Japanese beetles that happens to like my blackberries in the summer. Modocc (talk) 13:11, 24 December 2024 (UTC)
I would say not necessarily a Japanese beetle, but almost certainly one of the other Scarab beetles, though with 35,000 species that doesn't help a lot. Looking at the infobox illustration in that article, 16. & 17., "Anisoplia segetum" looks very similar, but evidently we either don't have an article or (if our Anisoplia article is a complete list) it's been renamed. {The poster formerly known as 87.81.230.195} 94.1.223.204 (talk) 14:18, 24 December 2024 (UTC)
Yes, it's not the Japanese beetle for this beetle appears to lack its white-dotted fringe although its condition is deteriorated. Its shape is also more or less more slender; and not as round. Modocc (talk) 15:02, 24 December 2024 (UTC)
Perhaps it is the shining leaf chafer Strigoderma pimalis. Shown here. Modocc (talk) 16:09, 24 December 2024 (UTC)
That looks like easily the best match I've seen so far, and likely correct. {The poster formerly known as 87.81.230.195} 94.1.223.204 (talk) 17:09, 24 December 2024 (UTC)

December 25

Categories: