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Chart looks rather out of date
The chart needs updating - as it ends in 2006 - missing the latest solar cycle. 131.111.23.90 (talk) 14:46, 7 April 2014 (UTC)
Historical perspective
Is this quote really helpful? First off, it talks about weather prediction, not climate. The quote itself is ambiguous, open to interpretation as either: "history has shown time and again that it is pseudo-science" or as "in those days it was seen as pseudo-science, but now we have a better understanding". The intro of the source text would be a better choice imo:
- Since it is the Sun's energy that drives the weather system, scientists naturally wondered whether they might connect climate changes with solar variations. Yet the Sun seemed to be stable over the timescale of human civilization. Attempts to discover cyclic variations in weather and connect them with the 11-year sunspot cycle, or other possible solar cycles ranging up to a few centuries long, gave results that were ambiguous at best. These attempts got a well-deserved bad reputation. Jack Eddy overcame this with a 1976 study that demonstrated that irregular variations in solar surface activity, a few centuries long, were connected with major climate shifts. The mechanism was uncertain, but plausible candidates emerged. Ssscienccce (talk) 20:18, 20 October 2013 (UTC)
- The article itself is rife with such conflicts. I don't expect an easy resolution. Batvette (talk) 12:50, 7 November 2013 (UTC)
Solar constant
The article states that "The amount of solar radiation received at the outer limits of Earth's atmosphere averages 1366 W/m." Yet the Misplaced Pages article on the solar constant gives the value of 1361 W/m. Can anyone explain the discrepancy? Thanks. Mhklein (talk) 20:11, 27 March 2014 (UTC)
- The lower estimate is more recent. Don't know if it is controversial. See Solar irradiation. Lfstevens (talk) 06:06, 16 July 2015 (UTC)
- I moved the order of these around slightly, to put the solar constant before the variation in solar constant, but didn't change the actual number without a canonical reference. Different sources do use slightly different totals. Several links were redirects to "solar irradiance", so I consolidated these to just one place. Geoffrey.landis (talk) 17:34, 19 July 2015 (UTC)
Predictions based on patterns
This section is a bit rubbish. Firstly, it "predicts" the 2010 peak, and no-one (including me!) has bothered update it for whatever happened. Secondly, its almost all about "predicting" climate (has it been copied in from elsewhere) not predicting the cycles, so it belongs under the climate heading William M. Connolley (talk) 08:15, 16 February 2015 (UTC)
Cosmic ray claim
Why is the stuff on cosmic rays in there? It doesn't apply to solar variation in any way. Lfstevens (talk) 16:41, 15 July 2015 (UTC)
- I'm not sure I understand the question. The sun's magnetic field deflects galactic cosmic rays. Thus, cosmic rays decrease with higher solar actitity. So this is related to solar variation.
- However, if you're just saying that there's too much on this subject for the article -- well, ok, maybe there is, and possibly it should be compressed and put into a single subsection, instead of spread over several.
- --by the way, you changed the term "galactic cosmic rays" to just "cosmic rays" in several places. I'm going to change those back-- the more generic term "cosmic rays" can also refer to solar proton events, which of course increase with solar activity. Geoffrey.landis (talk) 20:37, 16 July 2015 (UTC)
Restructure proposal
Surfaceology is an emerging field within condensed matter physics and mathematics, notable for its approach to calculating scattering amplitudes in quantum field theory. It hypothesizes a deep connection between geometry, topology, and particle physics.
Surfaceology may be able to replace Feynman diagrams, which translate into complex equations for describing particle interactions. Surfaceology yields the same result by in effect assembling multitudes of Feynman diagrams into a more compact representation. Surfaceology does not make use of supersymmetry and can describe both supersymmetric and nonsupersymmetric particles.
Background
Surfaceology is one of a host of theories that attempt to replace conventional notions of spacetime with more fundamental concepts.
Alternatives include string theory, branes,
Standard model
The standard model of physics (connections, curvature, spinors, the Dirac operator, quantization), is based in part on symmetries: properties that do not change when an object is subjected to space-time translations, such as a 90-degree rotation. Each particle has other internal symmetries, such as electric charge. The many decades of unsuccessful attempts to merge general relativity theory with quantum mechanics have led some theorists to attempt to discard the notion of space-time in favor of potentially more fundamental concepts. Others cotinue to try to solve the puzzle with space-time intact. The traditional issue is that general relativity does not describe events happening at very short distances, while quantum mechanics fails at the long distances at which general relativity is unmatched. The standard model exploits strong parallels between highly precise experimental observation and unrelated mathematical insights. The classical notion of spacetime is based on the Riemannian geometry of spinors, which emerged long before its application to physics was established. In particular, it relies on the notion of a space, including spin, the principal bundle of spin-frames with spin-connection and Vielbein dynamical variables.
Unsolved mysteries
Conventional space-time physics cannot describe the beginning of the universe.
A full quantum gravity theory known as a “nonperturbative” theory would also explain black holes.
Definition and scope
Surfaceology involves using curve integrals to compute scattering amplitudes, which are crucial in understanding how particles interact at a quantum level. This method simplifies and potentially revolutionizes how physicists approach these calculations by focusing on the geometry of surfaces outside of traditional three-dimensional space and time.
History
In the late 1940s, Schwinger, Tomonaga, and Feynman won the 1965 Nobel Prize for their work on quantum electrodynamics. Feynman’s scheme was the most visual and dominated quantum physics.
In the early 2000s, Nima Arkani-Hamed began looking for solutions. In the mid-2000s, Britto, Cachazo, Feng, and Witten discovered recursion relations, showing how to condense hundreds of Feynman diagrams to simple lines in specific situations.
In 2013, Arkani-Hamed and Trnka discovered the amplituhedron, a geometric object that describes the outcomes of certain particle interactions. However, the object only applied to world particles. Arkani-Hamad showed that in special cases, the amplitude (measure of change) of an interaction could be derived without knowing how the particles moved in space-time. Arkani-Hamed’s team later found that associahedrons worked in a similar way.
In 2019, Arkani-Hamed recruited mathematicians Salvatori and Hadleigh Frost to help look for a geometrical means to computing all such amplitudes.
In the fall of 2022 Carolina Figueiredo discovered that the same debris resulted from collisions involving three distinct types of subatomic particles. This led to the discovery that the nominally independent theories describing those particles were essentially the same.
In September 2023 Arkai-Hamed's group published their findings, still unable to describe real particles. Figueiredo then joined the group.
In 2024 Paranjape, et.al., showed that theories that can be double-copied have Figueiredo's zeros. Bourjaily then extended Figueiredo's approach to collisions involving up to 14 particles.
- Quantum Geometry: Geometric objects can encode the outcomes of quantum particle collisions across different theoretical universes.
- Mathematical Innovations: scalar-scaffolded gluons and the combinatorial origins of Yang-Mills theory can be understood through surfaceology.
Quantum interactions
Colliding quantum particles can merge, split, disappear, or combine in any order. Feynman diagrams describe such interactions by drawing lines representing the particles’ trajectories through space-time. Each diagram captures one possible event sequence and is accompanied by an amplitude equation that yields a number representing the odds of that sequence taking place. The theory states that macro-scale objects can be described by accumulating sufficient amplitudes.
One feature that has not been explained is that combining the equations for a large number of interactions may produce terms that cancel out, leaving simple answers—notably, a value of 1.
Objects
Amplituhedron
An amplituhedron is a shape that encodes the number and orientation of particles involved in a collision. Its volume gives the collision's amplitude. This volume is the sum of the associated Feynman diagrams' amplitudes, which depict ways that the collision could evolve, using the momenta of the particles from before and after the interaction, but crucially without reference to spatiotemporal dynamics. However, the amplituhedron applies only to supersymmetric particles.
Associahedron
An associahedron is a separate shape, displaying flat sides, whose volume gives amplitudes for a simplified quantum theory. The particles covered by this theory carry “color”, a type of charge also carried by quarks and gluons, but lack superpartners. Associahedrons produce amplitudes for only short event sequences.
Construction
These shapes can be defined by polynomials (equations that sum a series of terms) that correspond to the curves on a surface. Each curve can be seen as a sequence of left and right turns. Splitting this sequence into small pieces generates the polynomial. Amplitudes can then be easily calculated using the equation along with experimental data.
To calculate the odds of e.g., two particles colliding to form three particles, any Feynman diagram that shows two particle trajectories entering and three exiting can be used. The lines are thickened to form a surface, and curves are drawn across the surface. This redescribes the moving particles as a static structure.
This procedure works for all collisions, including those with lengthy event sequences. More complicated interactions may imply surfaces with holes that the curves loop around. The curves also correspond to the faces of an associahedron, establishing that the associahedron and surfaceology reflect the same mathematics.
Zeros
Arkani-Hamed provided solutions for one supersymmetric theory and another theory—trace Φ—which have amplitudes that take the form of fractions. All their variables (particle momentums,...) fall in the denominator and work for simplified particles. However, quantum theories that describe real particles also require variables in the numerator. For example, electrons have spin (intrinsic angular momentum) and terms that capture spin sit in the numerator.
Collision singularities are collisions with small denominators and correspondingly high amplitudes. They are important facets of any quantum theory.
Figueiredo discovered that fractions with small numerators could help find the geometric underpinnings of real particle interactions. Such amplitudes approach zero, representing collisions with minute probabilities. Such “zeros” have difficult Feynman diagrams, and are definitionally hard to observe experimentally. She identified zeros of trace Φ by converting amplitudes into low volume associahedrons of varying sets of input and output particles. She then checked pion collisions—collisions of real particles, and showed that they had the same zeros. Pions have no known geometric theory, offering no alternative to Feynman diagrams. The same collisions were zeros under the Yang-Mills theory of gluons.
The curves of trace Φ theory give an equation for an amplitude. Only one part of the equation can change while preserving the zeros; producing one of the three particles (trace Φ, pions, or gluons).
Initially, surfaceology described only collisions among bosons, which have integer spin. Fermions (including electrons) instead have half-integer spin. Spradlin, Volovich, and Skowronek worked out rules for curves that can accommodate simplified fermion models.
Double copy
Some quantum theories allow "double copies", in which two amplitudes of one theory combine to make an amplitude of another theory. Theories that can be double-copied have Figueiredo's zeros.
String theory
Self-intersecting curves produce an unusual amplitude, which describe interactions between strings instead of particles. Thus, surfaceology may offer another route to string theory, a proposed theory of quantum gravity that sees quantum particles as vibrating strings of energy.
Gravity
Surfaceology might apply to quantum gravity. On hole-bearing surfaces, some curves that do not affect the result infinitely circle the holes. Surfaceology curves capture events beyond trace Φ theory. They describe colorless particles that could match gravitons, hypothetical particles theorized to produce the gravitational force.
Related theories
Holography
Holographic theories seek to capture the entirety of space-time. They treat it as a hologram of quantum particles moving in a space of one less dimension. Holographic theories may explain the interiors of black holes and how one spatial dimension could emerge. It depends on traditional quantum objects: space, locality, and a clock, instead of letting those objects emerge as features of the theory.
Twistors
Twistors are a mathematically equivalent picture of space-time. Physical phenomena in space-time can be described in twistor space, or vice versa. Penrose showed that they simplify certain physical calculations. One unexplained aspect of twistor space is that certain particles can be either “right-handed” or “left-handed,” depending on whether they follow their spin through space. However Twistor space best fits theories of purely right-handed or purely left-handed particles, rather than incorporating both types of particles and their interactions.
Colored Yukawa theory
Scattering amplitudes for colored theories can be expressed as integrals over combinatorial objects constructed from surfaces decorated by kinematic data. The curve integral formalism includes theories with colored fermionic matter. A compact formula describes the all-loop, all-genus, all-multiplicity amplitude integrand of a colored Yukawa theory. The curve integral formalism manifests certain properties of the amplitudes. Non-trivial numerators can be merged into a single combinatorial object. Loop integrated amplitudes can be computed in terms of a sum over combinatorial determinants.
Applications
Potential applications include understanding phenomena such as the behavior of surfaces (e.g., how a surface wrinkles depending on its curvature) and could lead to insights in areas such as nanotechnology.
References
- Wood, Charlie (2024-09-25). "Physicists Reveal a Quantum Geometry That Exists Outside of Space and Time". Quanta Magazine. Retrieved 2024-11-06.
- ^ Hamilton, Richard S. (2024-09-26). "Is Spacetime Unraveling?". Not Even Wrong. Retrieved 2024-12-01.
- Wood, Charlie (2024-09-25). "Can Space-Time Be Saved?". Quanta Magazine. Retrieved 2024-12-01.
- Institute for Advanced Study (2024-06-12). Hidden Zeros and the Double Copy - Shruti Paranjape. Retrieved 2024-12-30 – via YouTube.
- De, Shounak; Pokraka, Andrzej; Skowronek, Marcos; Spradlin, Marcus; Volovich, Anastasia (2024-09-20), Surfaceology for Colored Yukawa Theory, doi:10.48550/arXiv.2406.04411, retrieved 2024-12-01
External links
- Musser, George (2015-11-03). Spooky Action at a Distance: The Phenomenon That Reimagines Space and Time--and What It Means for Black Holes, the Big Bang, and Theories of Everything. Macmillan. ISBN 978-0-374-29851-7.
- Musser, George (2023-11-09). Putting Ourselves Back in the Equation: Why Physicists Are Studying Human Consciousness and AI to Unravel the Mysteries of the Universe. Simon and Schuster. ISBN 978-0-86154-720-3.
- Musser, George (2017-05-16). "A Defense of the Reality of Time". Quanta Magazine. Retrieved 2024-12-01.
- Horgan, John (October 3, 2024). "The Beyond-Spacetime Meme". John Horgan (The Science Writer). Retrieved 2024-12-01.
https://www.unilad.com/news/health/reversible-cancer-cell-therapy-normal-kwang-hyun-cho-540530-20241227 https://pmc.ncbi.nlm.nih.gov/articles/PMC10835663/ https://newatlas.com/cancer/cancer-cells-normal/