computronium
{{Short description|Best form of computing device}}
Computronium is a material hypothesized by Norman Margolus and Tommaso Toffoli of MIT in 1991 to be used as "programmable matter", a substrate for computer modeling of virtually any real object.{{Cite journal|last=Amato|first=I.|date=1991-08-23|title=Speculating in Precious Computronium|url=https://www.science.org/doi/10.1126/science.253.5022.856|journal=Science|language=en|volume=253|issue=5022|pages=856–857|doi=10.1126/science.253.5022.856|pmid=17751817|bibcode=1991Sci...253..856A|s2cid=43676333|issn=0036-8075|url-access=subscription}}
It also refers to an arrangement of matter that is the best possible form of computing device for that amount of matter.[http://www.singinst.org/upload/CFAI//info/glossary.html#gloss_computronium CFAI glossary: computronium] {{webarchive|url=https://web.archive.org/web/20100420013420/http://singinst.org/upload/CFAI/info/glossary.html |date=2010-04-20 }} In this context, the term can refer both to a theoretically perfect arrangement of hypothetical materials that would have been developed using nanotechnology at the molecular, atomic, or subatomic level (in which case this interpretation of computronium could be unobtainium{{Cite web |last=Cake |first=Suzanne Gildert-Physics and |date=2011-02-11 |title=Why "Computronium" is really "Unobtanium" |url=https://gizmodo.com/why-computronium-is-really-unobtanium-5758349 |access-date=2022-09-03 |website=Gizmodo |language=en-us}}{{Cite web |date=2011-03-08 |title=Computronium is claimed to be unobtanium {{!}} NextBigFuture.com |url=https://www.nextbigfuture.com/2011/03/computronium-is-claimed-to-be.html |access-date=2022-09-03 |language=en-US}}), and to the best possible achievable form using currently available and used computational materials.
According to the Barrow scale, a modified variant of the Kardashev scale created by British physicist John D. Barrow, which is intended to categorize the development stage of extraterrestrial civilizations, it would be conceivable that advanced civilizations do not claim more and more space and resources, but optimize their already available space increasingly, for example by building a matrioshka brain consisting of several layers of computronium around their star.{{Cite web |last=Williams |first=Matt |date=2022-03-13 |title=What is the Kardashev Scale? |url=https://www.universetoday.com/153167/what-is-the-kardashev-scale/ |access-date=2022-06-23 |website=Universe Today |language=en-US}}
In the 2010 film The Singularity Is Near: A True Story About the Future, American futurist Ray Kurzweil discusses a universe filled with computronium.{{Cite web|title=Computronium universe - computation limits of computronium and limits to the universe {{!}} NextBigFuture.com|url=https://www.nextbigfuture.com/2018/04/computronium-universe-computation-limits-of-computronium-and-limits-to-the-universe.html|access-date=2021-06-13|language=en-US}} He believes this could be possible as early as the late 22nd century and would be accomplished by sending intelligent nanobots through the universe faster than light, e.g. by using wormholes. According to him, such an endeavor would have the potential to prevent the natural ending of the universe.
In addition, the term computronium is used in connection with science fiction narratives.{{Cite journal |last=Patra |first=Indrajit |date=2019-01-01 |title=Going Beyond the Limits: Exploring the Elements of Posthumanism, Transhumanism and Singularity in Some Select Hard Science Fiction Novels of the 21st Century |url=https://www.academia.edu/45011952 |journal=Going Beyond the Limits: Exploring the Elements of Posthumanism, Transhumanism and Singularity in Some Select Hard Science Fiction Novels of the 21st Century}}