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{{pp-vandalism|small=yes}}
{{two other uses||the Internet company|Google|the Russian author|Nikolai Gogol}}
{{Short description|Large number defined as ten to the 100th power}}
A '''googol''' is the ] 10<sup>100</sup>, that is, the ] 1 followed by one hundred ] (in ] representation).
{{distinguish|text=] or ]}}
The term was coined in 1938<ref>Kasner, Edward and James Newman, ''Mathematics and the Imagination,'' ], Simon and Schuster, New York. ISBN 0-486-41703-4</ref> by Milton Sirotta (1929–1980), nephew of American ] ]. Kasner popularized the concept in his book ''Mathematics and the Imagination'' (1940).
A '''googol''' is the ] 10<sup>100</sup> or ten to the power of one&nbsp;hundred. In decimal notation, it is written as the ] 1 followed by one hundred ]s: <!-- Do not use ], it breaks mobile -->'''10,{{wbr}}000,{{wbr}}000,{{wbr}}000,{{wbr}}000,{{wbr}}000,{{wbr}}000,{{wbr}}000,{{wbr}}000,{{wbr}}000,{{wbr}}000,{{wbr}}000,{{wbr}}000,{{wbr}}000,{{wbr}}000,{{wbr}}000,{{wbr}}000,{{wbr}}000,{{wbr}}000,{{wbr}}000,{{wbr}}000,{{wbr}}000,{{wbr}}000,{{wbr}}000,{{wbr}}000,{{wbr}}000,{{wbr}}000,{{wbr}}000,{{wbr}}000,{{wbr}}000,{{wbr}}000,{{wbr}}000,{{wbr}}000,{{wbr}}000'''. Its ] is '''ten duotrigintillion''' (]) or '''ten sexdecilliard''' (]). Its ] is 2<sup>100</sup>&nbsp;×&nbsp;5<sup>100</sup>.


==Etymology==
Googol is of the same ] as the ] of 70 (70! being approximately 1.198 googol, or 10 to the power 100.0784), and its only ]s are 2 and 5 (100 of each). In ] it would take up 333 ]s.
The term was coined in 1920 by 9-year-old Milton Sirotta (1911–1981), nephew of American mathematician ].<ref>{{cite journal|last=Bialik |first=Carl |url=https://www.wsj.com/articles/SB108575924921724042 |title=There Could Be No Google Without Edward Kasner |journal=The Wall Street Journal Online |date=June 14, 2004 |url-status=live |archive-url=https://web.archive.org/web/20161130145858/http://www.wsj.com/articles/SB108575924921724042 |archive-date=November 30, 2016}}</ref> He may have been inspired by the contemporary comic strip character ].<ref>{{cite book |title=The Hidden History of Coined Words |author1=Ralph Keyes |edition= |publisher=Oxford University Press |year=2021 |isbn=978-0-19-046677-0 |page=120 |url=https://books.google.com/books?id=JYskEAAAQBAJ}} </ref> Kasner popularized the concept in his 1940 book '']''.<ref>{{cite book| author1 = Kasner, Edward| author2 = Newman, James R.| title = Mathematics and the Imagination| url = https://books.google.com/books?id=Ad8hAx-6m9oC&q=Mathematics%20and%20the%20Imagination&pg=PP1| year = 1940| publisher = Simon and Schuster, New York| isbn = 0-486-41703-4| url-status = live| archive-url = https://web.archive.org/web/20140703073029/http://books.google.com/books?id=Ad8hAx-6m9oC&lpg=PP1&dq=Mathematics%20and%20the%20Imagination&pg=PP1| archive-date = 2014-07-03}} The relevant passage about the googol and googolplex, attributing both of these names to Kasner's nine-year-old nephew, is available in {{cite book|editor=James R. Newman |title=The world of mathematics |volume=3 |year=2000 |publisher=Dover Publications |location=Mineola, New York |orig-year=1956 |isbn=978-0-486-41151-4 |pages=2007–2010}}</ref> Other ] for this quantity include ''ten duotrigintillion'' on the ] (commonly used in English speaking countries),<ref>{{cite book |last1=Bromham |first1=Lindell |title=An Introduction to Molecular Evolution and Phylogenetics |date=2016 |publisher=Oxford University Press |location=New York, NY |isbn=978-0-19-873636-3 |page=494 |edition=2nd |url=https://books.google.com/books?id=Jf9NCwAAQBAJ |access-date=April 15, 2022}}</ref> ''ten thousand sexdecillion'' on the ], or ''ten sexdecilliard'' on the ].
A googol has no particular significance in ], but is useful when comparing with other incredibly large quantities such as the number of subatomic particles in the visible universe or the number of possible ] games. ] created it to illustrate the difference between an unimaginably large number and ], and in this role it is sometimes used in teaching mathematics.


== Size ==
A '''googol''' can be written in conventional notation as follows:
A googol has no special significance in mathematics. However, it is useful when comparing with other very large quantities, such as the number of ] in the visible universe or the number of hypothetical possibilities in a ] game. Kasner used it to illustrate the difference between an unimaginably large number and ], and in this role it is sometimes used in teaching mathematics. To put in perspective the size of a googol, the mass of an electron, just under 10<sup>-30</sup>&nbsp;kg, can be compared to the mass of the visible universe, estimated at between 10<sup>50</sup> and 10<sup>60</sup>&nbsp;kg.<ref>{{cite web|url=https://hypertextbook.com/facts/2006/KristineMcPherson.shtml |title=Mass of the universe |first=Kristine |last=McPherson |year=2006 |website=The Physics Factbook |editor-last=Elert |editor-first=Glenn |access-date=2019-08-24}}</ref> It is a ratio in the order of about 10<sup>80</sup> to 10<sup>90</sup>, or at most one ten-billionth of a googol (0.00000001% of a googol).


] pointed out that the total number of elementary particles in the universe is around 10<sup>80</sup> (the ]) and that if the whole universe were packed with ]s so that there would be no empty space anywhere, there would be around 10<sup>128</sup>. He also noted the similarity of the second calculation to that of ] in '']''. By Archimedes's calculation, the universe of ] (roughly 2&nbsp;light years in diameter), if fully packed with sand, would contain 10<sup>63</sup>&nbsp;grains. If the much larger observable universe of today were filled with sand, it would still only equal {{val|e=95}}&nbsp;grains. Another 100,000 observable universes filled with sand would be necessary to make a googol.<ref>{{cite book|last=Sagan|first=Carl|author-link=Carl Sagan|title=Cosmos|year=1981|publisher=Book Club Associates|pages=220–221}}</ref>
:1 googol
:= 10<sup>100</sup>
:=&nbsp;<small>'''10,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000'''</small>
Its official English ] is '''ten duotrigintillion''' on the ], '''ten thousand sexdecillion''' on the ], or '''ten sexdecilliard''' on the ].


The decay time for a supermassive ] of roughly 1&nbsp;galaxy-mass (10<sup>11</sup>&nbsp;]) due to ] is on the order of 10<sup>100</sup>&nbsp;years.<ref name="page">{{cite journal|last=Page |first=Don N. |title=Particle emission rates from a black hole: Massless particles from an uncharged, nonrotating hole |journal=Physical Review D |publisher=American Physical Society (APS) |volume=13 |issue=2 |date=1976-01-15 |issn=0556-2821 |doi=10.1103/physrevd.13.198 |pages=198–206|bibcode=1976PhRvD..13..198P}} See in particular equation (27).</ref> Therefore, the ] of an ] is lower-bounded to occur at least one googol&nbsp;years in the future.
==Googolplex ==
{{Main|Googolplex}}
A googolplex is the number one followed by one googol zeroes, or ten raised to the power of one googol:
:10<sup>googol</sup> = 10<sup>(10<sup>100</sup>)</sup>.


A googol is considerably smaller than a ].<ref>{{cite book |last1=Stewart |first1=Ian |title=Infinity: A Very Short Introduction |date=2017 |publisher=Oxford University Press |location=New York, NY |isbn=978-0-19-875523-4 |page=20 |url=https://books.google.com/books?id=iewwDgAAQBAJ |access-date=April 15, 2022}}</ref>
In the documentary ], physicist and broadcast personality ] estimated that writing a googolplex in numerals (i.e., "1,000,000,000...") would be physically impossible, since doing so would require more space than the known universe occupies.


== Properties ==
==Googol and comparable large numbers==
A googol is approximately equal to <math>70!\approx1.1979\times10^{100}</math> (] of 70). Using an ], ], one would need 333&nbsp;bits to represent a googol, i.e., <math>10^{100}=2^{(100/\mathrm{log}_{10}2)}\approx2^{332.19280949}</math>. However, a googol is well within the maximum bounds of an IEEE&nbsp;754 ] type without full precision in the mantissa.


Using ], the series of ] (mod&nbsp;''n'') of one&nbsp;googol, starting with mod&nbsp;1, is as follows:
A googol is greater than the number of atoms in the ], which has been variously estimated from 10<sup>79</sup> up to 10<sup>81</sup> <ref> of the number of atoms in the Universe; 10<sup>78</sup> up to 10<sup>81</sup></ref><ref> of the number of atoms in the Universe; 4&nbsp;×&nbsp;10<sup>79</sup></ref>. Less than a googol ]s have elapsed since the ] (the current figure stands at around 8×10<sup>60</sup> Planck times). From the previous two figures, it can be seen that a list of where every particle is at every possible discernible unit of time since the ] would contain over a googol entries, but still far less than a googolplex: around 8&nbsp;×&nbsp;10<sup>140</sup>.


:0, 0, 1, 0, 0, 4, 4, 0, 1, 0, 1, 4, 3, 4, 10, 0, 4, 10, 9, 0, 4, 12, 13, 16, 0, 16, 10, 4, 16, 10, 5, 0, 1, 4, 25, 28, 10, 28, 16, 0, 1, 4, 31, 12, 10, 36, 27, 16, 11, 0,&nbsp;... {{OEIS|id=A066298}}
A ''little googol'' is 2<sup>100</sup> (about 1.268{{e|30}}), or 1,267,650,600,228,229,401,496,703,205,376, while a ''little googolplex'' is <math>2^{2^{100}}</math> or about <math>10^{3.8 \times 10^{29}}</math>.


This sequence is the same as that of the ] of a ] up until the 17th position.
], 6.02214179{{e|23}}, is exactly the number of ] atoms in 12 grams (0.012 kg) of unbound <sup>12</sup>C in its ground state. It is perhaps the most widely known large number from ] and ]. Avogadro's number is less than the fourth root of a googol.


== Cultural impact ==
]s are presumed to evaporate because they faintly give off ]; if so, a ] would take ''about'' a googol years to evaporate.<ref>, p.4</ref>
Widespread sounding of the word occurs through the name of the company ], with the name "Google" being an accidental misspelling of "googol" by the company's founders,<ref>{{cite web |url=http://graphics.stanford.edu/~dk/google_name_origin.html |title=Origin of the name "Google" |last=Koller |first=David |date=January 2004 |publisher=Stanford University |access-date=July 4, 2012 |archive-url=https://web.archive.org/web/20120627081942/http://graphics.stanford.edu/~dk/google_name_origin.html |archive-date=June 27, 2012 |url-status=dead }}</ref> which was picked to signify that the search engine was intended to provide large quantities of information.<ref>{{cite web|url=https://www.google.com/company.html |title=Google! Beta website |publisher=Google, Inc. |archive-url=https://web.archive.org/web/19990221202430/http://www.google.com/company.html |archive-date=February 21, 1999 |access-date=October 12, 2010 |url-status=dead }}</ref> In 2004, family members of Kasner, who had inherited the right to his book, were considering suing Google for their use of the term "googol";<ref>{{cite web|title= Have your Google people talk to my 'googol' people|date= 16 May 2004|url= https://www.baltimoresun.com/2004/05/16/have-your-google-people-talk-to-my-googol-people/|url-status= live|archive-url= https://web.archive.org/web/20140904125042/http://articles.baltimoresun.com/2004-05-16/entertainment/0405150243_1_google-googol-internet-search-engine|archive-date= 2014-09-04}}</ref> however, no suit was ever filed.<ref>{{Cite book |last=Nowlan |first=Robert A. |title=Masters of Mathematics: The Problems They Solved, Why These Are Important, and What You Should Know about Them |publisher=Sense Publishers |year=2017 |isbn=978-9463008938 |location=Rotterdam |pages=221 |language=en}}</ref>


Since October 2009, Google has been assigning domain names to its servers under the domain "1e100.net", the scientific notation for 1&nbsp;googol, in order to provide a single domain to identify servers across the Google network.<ref>{{cite web |url=https://www.theregister.co.uk/2010/02/08/google_mystery_domain/ |title=Google doppelgänger casts riddle over interwebs |date=8 February 2010 |access-date=30 December 2015 |publisher=The Register |author=Cade Metz |url-status=live |archive-url=https://web.archive.org/web/20160303180937/https://www.theregister.co.uk/2010/02/08/google_mystery_domain/ |archive-date=3 March 2016 }}</ref><ref>{{cite web |url=https://support.google.com/faqs/answer/174717?hl=en |title=What is 1e100.net? |access-date=30 December 2015 |publisher=Google Inc. |url-status=live |archive-url=https://web.archive.org/web/20160109065331/https://support.google.com/faqs/answer/174717?hl=en |archive-date=9 January 2016 }}</ref>
Seventy ], or 70!, is "just 1.19785717&nbsp;×&nbsp;10<sup>100</sup>. This means that there are over a googol ways to arrange seventy items (or people) in a sequence (such as a line to a ]).


The word is notable for being the subject of the £1&nbsp;million question in a 2001 episode of the British quiz show '']'', when contestant ] was discovered to have ] with the help of a confederate in the studio audience.<ref>{{citation|title=Television's Strangest Moments: Extraordinary But True Tales from the History of Television|first1=Quentin|last1=Falk|first2=Ben|last2=Falk|publisher=Franz Steiner Verlag|year=2005|isbn=9781861058744|url=https://books.google.com/books?id=4L7pA2tKumsC&pg=PA245|pages=245–246|contribution=A Code and a Cough: Who Wants to Be a Millionaire? (1998–)}}.</ref>
The ], 10<sup>120</sup>, a rough lower bound on the number of possible chess games, is more than a googol.

A googol is considerably less than the number described in the ancient ]' story of ], namely <math>\left((10^8)^{(10^8)}\right)^{(10^8)}=10^{8\cdot 10^{16}}.</math> But it should be noted that the system invented by ] is reminiscent of a ] with base 10<sup>8</sup>, so that ]' number could be written <math>\left_{10^8}=\left_{10^8}</math>, that is, one googol in base 10<sup>8</sup>

==Higher numbers==
Other numbers related to the googol number have been circulating. Some are:

Googolplexian: a one followed by a googolplex of zeroes.

Googolcomplexity: a one and a googolplexian of zeroes.

Even the googolplex could not be written in the entire space of the universe, so these number are of course extremely, possibly even illogically high.

==In popular culture==

''Googol'' was the answer to the million-] question: ''"A number one followed by 100 zeros is known by what name?"'' on '']'' when ] allegedly attempted to defraud the quiz show on ] ]. The other options were a ], a ] or a nanomole.<ref></ref>

''Googol'' is one of the 336 vocabulary words in the board game Balderdash, and their definition on the back of the card is "The number one followed by 100 zeros."

In the ], ] '']'' strip, Lucy asks Schroeder what the chances are of them getting married, and Schroeder responds "Oh, I'd say about 'googol' to one."

In an episode of the animated series '']'', the "Gaminator" video games system is said to have a "3-googolhertz processor."

"A googol is precisely as far from infinity as is the number one." — ], '']''

The company name ] is a misspelling of the word "Googol" made by founders Larry Page and Sergey Brin, as described in the book ''The Google Story'' by ].


==See also== ==See also==
*] * ]
*] * ]
*] * ]
* ]
* ]


==References== ==References==
{{Reflist|30em}}
<!-- This article uses ]. Please use this format in the article text when inserting references. Any external link inserted directly into this section will be swiftly deleted. -->{{reflist|2}}


==External links== ==External links==
{{Wiktionary}}
*
* {{MathWorld | urlname=Googol | title=Googol}} * {{MathWorld|urlname=Googol|title=Googol}}
* {{PlanetMath | urlname=Googol | title=googol}} * {{PlanetMath|urlname=Googol|title=Googol}}
* {{cite web|title=Googol and Googolplex|url=http://www.numberphile.com/videos/googolplex.html|work=Numberphile|publisher=]|author=Padilla, Tony|author2=Symonds, Ria|access-date=2013-04-06|archive-url=https://web.archive.org/web/20140329024608/http://www.numberphile.com/videos/googolplex.html|archive-date=2014-03-29|url-status=dead}}
* by Paul Niquette


] {{Large numbers}}

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Latest revision as of 19:24, 12 November 2024

Large number defined as ten to the 100th power Not to be confused with Google or Nikolai Gogol.

A googol is the large number 10 or ten to the power of one hundred. In decimal notation, it is written as the digit 1 followed by one hundred zeroes: 10,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000. Its systematic name is ten duotrigintillion (short scale) or ten sexdecilliard (long scale). Its prime factorization is 2 × 5.

Etymology

The term was coined in 1920 by 9-year-old Milton Sirotta (1911–1981), nephew of American mathematician Edward Kasner. He may have been inspired by the contemporary comic strip character Barney Google. Kasner popularized the concept in his 1940 book Mathematics and the Imagination. Other names for this quantity include ten duotrigintillion on the short scale (commonly used in English speaking countries), ten thousand sexdecillion on the long scale, or ten sexdecilliard on the Peletier long scale.

Size

A googol has no special significance in mathematics. However, it is useful when comparing with other very large quantities, such as the number of subatomic particles in the visible universe or the number of hypothetical possibilities in a chess game. Kasner used it to illustrate the difference between an unimaginably large number and infinity, and in this role it is sometimes used in teaching mathematics. To put in perspective the size of a googol, the mass of an electron, just under 10 kg, can be compared to the mass of the visible universe, estimated at between 10 and 10 kg. It is a ratio in the order of about 10 to 10, or at most one ten-billionth of a googol (0.00000001% of a googol).

Carl Sagan pointed out that the total number of elementary particles in the universe is around 10 (the Eddington number) and that if the whole universe were packed with neutrons so that there would be no empty space anywhere, there would be around 10. He also noted the similarity of the second calculation to that of Archimedes in The Sand Reckoner. By Archimedes's calculation, the universe of Aristarchus (roughly 2 light years in diameter), if fully packed with sand, would contain 10 grains. If the much larger observable universe of today were filled with sand, it would still only equal 10 grains. Another 100,000 observable universes filled with sand would be necessary to make a googol.

The decay time for a supermassive black hole of roughly 1 galaxy-mass (10 solar masses) due to Hawking radiation is on the order of 10 years. Therefore, the heat death of an expanding universe is lower-bounded to occur at least one googol years in the future.

A googol is considerably smaller than a centillion.

Properties

A googol is approximately equal to 70 ! 1.1979 × 10 100 {\displaystyle 70!\approx 1.1979\times 10^{100}} (factorial of 70). Using an integral, binary numeral system, one would need 333 bits to represent a googol, i.e., 10 100 = 2 ( 100 / l o g 10 2 ) 2 332.19280949 {\displaystyle 10^{100}=2^{(100/\mathrm {log} _{10}2)}\approx 2^{332.19280949}} . However, a googol is well within the maximum bounds of an IEEE 754 double-precision floating point type without full precision in the mantissa.

Using modular arithmetic, the series of residues (mod n) of one googol, starting with mod 1, is as follows:

0, 0, 1, 0, 0, 4, 4, 0, 1, 0, 1, 4, 3, 4, 10, 0, 4, 10, 9, 0, 4, 12, 13, 16, 0, 16, 10, 4, 16, 10, 5, 0, 1, 4, 25, 28, 10, 28, 16, 0, 1, 4, 31, 12, 10, 36, 27, 16, 11, 0, ... (sequence A066298 in the OEIS)

This sequence is the same as that of the residues (mod n) of a googolplex up until the 17th position.

Cultural impact

Widespread sounding of the word occurs through the name of the company Google, with the name "Google" being an accidental misspelling of "googol" by the company's founders, which was picked to signify that the search engine was intended to provide large quantities of information. In 2004, family members of Kasner, who had inherited the right to his book, were considering suing Google for their use of the term "googol"; however, no suit was ever filed.

Since October 2009, Google has been assigning domain names to its servers under the domain "1e100.net", the scientific notation for 1 googol, in order to provide a single domain to identify servers across the Google network.

The word is notable for being the subject of the £1 million question in a 2001 episode of the British quiz show Who Wants to Be a Millionaire?, when contestant Charles Ingram was discovered to have cheated his way through the show with the help of a confederate in the studio audience.

See also

References

  1. Bialik, Carl (June 14, 2004). "There Could Be No Google Without Edward Kasner". The Wall Street Journal Online. Archived from the original on November 30, 2016.
  2. Ralph Keyes (2021). The Hidden History of Coined Words. Oxford University Press. p. 120. ISBN 978-0-19-046677-0. Extract of page 120
  3. Kasner, Edward; Newman, James R. (1940). Mathematics and the Imagination. Simon and Schuster, New York. ISBN 0-486-41703-4. Archived from the original on 2014-07-03. The relevant passage about the googol and googolplex, attributing both of these names to Kasner's nine-year-old nephew, is available in James R. Newman, ed. (2000) . The world of mathematics. Vol. 3. Mineola, New York: Dover Publications. pp. 2007–2010. ISBN 978-0-486-41151-4.
  4. Bromham, Lindell (2016). An Introduction to Molecular Evolution and Phylogenetics (2nd ed.). New York, NY: Oxford University Press. p. 494. ISBN 978-0-19-873636-3. Retrieved April 15, 2022.
  5. McPherson, Kristine (2006). Elert, Glenn (ed.). "Mass of the universe". The Physics Factbook. Retrieved 2019-08-24.
  6. Sagan, Carl (1981). Cosmos. Book Club Associates. pp. 220–221.
  7. Page, Don N. (1976-01-15). "Particle emission rates from a black hole: Massless particles from an uncharged, nonrotating hole". Physical Review D. 13 (2). American Physical Society (APS): 198–206. Bibcode:1976PhRvD..13..198P. doi:10.1103/physrevd.13.198. ISSN 0556-2821. See in particular equation (27).
  8. Stewart, Ian (2017). Infinity: A Very Short Introduction. New York, NY: Oxford University Press. p. 20. ISBN 978-0-19-875523-4. Retrieved April 15, 2022.
  9. Koller, David (January 2004). "Origin of the name "Google"". Stanford University. Archived from the original on June 27, 2012. Retrieved July 4, 2012.
  10. "Google! Beta website". Google, Inc. Archived from the original on February 21, 1999. Retrieved October 12, 2010.
  11. "Have your Google people talk to my 'googol' people". 16 May 2004. Archived from the original on 2014-09-04.
  12. Nowlan, Robert A. (2017). Masters of Mathematics: The Problems They Solved, Why These Are Important, and What You Should Know about Them. Rotterdam: Sense Publishers. p. 221. ISBN 978-9463008938.
  13. Cade Metz (8 February 2010). "Google doppelgänger casts riddle over interwebs". The Register. Archived from the original on 3 March 2016. Retrieved 30 December 2015.
  14. "What is 1e100.net?". Google Inc. Archived from the original on 9 January 2016. Retrieved 30 December 2015.
  15. Falk, Quentin; Falk, Ben (2005), "A Code and a Cough: Who Wants to Be a Millionaire? (1998–)", Television's Strangest Moments: Extraordinary But True Tales from the History of Television, Franz Steiner Verlag, pp. 245–246, ISBN 9781861058744.

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