{{Short description|Mathematical instability in string theory}} In theoretical physics, a '''bubble of nothing''' is a physical instability that is found in higher-dimensional spacetime models. It was first described by Edward Witten in 1982, as a consequence of the positive energy theorem.<ref>{{Cite journal |last=Witten |first=Edward |date=1982-02-22 |title=Instability of the Kaluza-Klein vacuum |url=https://www.sciencedirect.com/science/article/pii/0550321382900074 |journal=Nuclear Physics B |volume=195 |issue=3 |pages=481–492 |doi=10.1016/0550-3213(82)90007-4 |issn=0550-3213|url-access=subscription }}</ref><ref name=":0">{{Cite web |last=Wood |first=Charlie |date=2022-08-09 |title=How the Physics of Nothing Underlies Everything |url=https://www.quantamagazine.org/how-the-physics-of-nothing-underlies-everything-20220809/ |access-date=2025-08-18 |website=Quanta Magazine |language=en}}</ref><ref name=":2" /> It represents a non-perturbative decay channel of Kaluza–Klein theory, in which spacetime can spontaneously collapse through the nucleation of a gravitational instanton.<ref name=":2">{{Cite book |last=Ong |first=Yen Chin |url=https://www.google.fr/books/edition/Evolution_of_Black_Holes_in_Anti_de_Sitt/M94LCwAAQBAJ?hl=en&gbpv=1&dq=bubble+of+nothing+witten+kaluza&pg=PA85&printsec=frontcover |title=Evolution of Black Holes in Anti-de Sitter Spacetime and the Firewall Controversy |date=2015-11-27 |publisher=Springer |isbn=978-3-662-48270-4 |language=en}}</ref> This bubble of nothing has no interior, not even spacetime.<ref name=":0" /><ref name=":2" />
Bubbles of nothing are forbidden in models that include supersymmetry.<ref name=":2" />
It has been considered as an hypothetical end of the universe mechanism.<ref name=":1">{{Cite web |last=Minsky |first=Carly |date=2020-03-05 |title=Physicists Are Studying Mysterious ‘Bubbles of Nothing’ That Eat Spacetime |url=https://www.vice.com/en/article/physicists-are-studying-mysterious-bubbles-of-nothing-that-eat-spacetime/ |access-date=2025-08-18 |website=VICE |language=en-US}}</ref> As bubbles of nothing have not been observed, their absence can be used to put constraints on other theories.<ref name=":1" />
==See also== * False vacuum ==References== {{Reflist}}
==External links== *{{YouTube|t8QonEChDGY|A bubble of absolute nothing}} by Sixty Symbols {{Physicist-stub}} Category:Physical cosmological concepts Category:String theory Category:Ultimate fate of the universe