Editing Googolplex (section)

===In the physical universe===
In the [[Public Broadcasting Service|PBS]] science program ''[[Cosmos: A Personal Voyage]]'', [[Cosmos: A Personal Voyage#Episode 9: "The Lives of the Stars"|Episode 9: "The Lives of the Stars"]], [[astronomer]] and television personality [[Carl Sagan]] estimated that writing a googolplex in full decimal form (i.e., "10,000,000,000...") would be physically impossible, since doing so would require more space than is available in the known universe. Sagan gave an example that if the entire volume of the [[observable universe]] is filled with fine [[Cosmic dust|dust particles]] roughly 1.5 micrometers in size (0.0015 millimeters), then the number of different [[combinations]] in which the particles could be arranged and numbered would be about one googolplex.<ref>[https://www.livescience.com/31981-googol.html "Googol, Googolplex - & Google" - LiveScience.com] {{Webarchive|url=https://web.archive.org/web/20200726041136/https://www.livescience.com/31981-googol.html |date=26 July 2020 }} 8 August 2020.</ref><ref>[https://www.space.com/41721-big-numbers-universe-photos/2.html "Large Numbers That Define the Universe" - Space.com] {{Webarchive|url=https://web.archive.org/web/20191102034608/https://www.space.com/41721-big-numbers-universe-photos/2.html |date=2 November 2019 }} 8 August 2020.</ref>

{{10^|97}} is a high estimate of the elementary particles existing in the visible universe (not including [[dark matter]]), mostly photons and other massless force carriers.<ref>{{cite web
 |author=Robert Munafo
 |date=24 July 2013
 |title=Notable Properties of Specific Numbers
 |url=http://mrob.com/pub/math/numbers-19.html
 |access-date=2013-08-28
 |archive-date=6 October 2020
 |archive-url=https://web.archive.org/web/20201006200300/http://mrob.com/pub/math/numbers-19.html
 |url-status=live
 }}</ref>