Editing Anti-gravity (section)

==Historical attempts at understanding gravity==
{{Main|History of gravitational theory}}
The possibility of creating anti-gravity depends upon a complete understanding and description of gravity and its interactions with other physical theories, such as [[general relativity]] and [[quantum mechanics]]; however, no quantum theory of gravity has yet been found.

During the summer of 1666, [[Isaac Newton]] observed an apple falling from the tree in his garden, thus realizing the [[Newton's law of universal gravitation|principle of universal gravitation]].<ref name="york">Department of Physics [https://www.york.ac.uk/physics/about/newtonsappletree/ A Brief History of Isaac Newton's Apple Tree], [[University of York]], Retrieved 2019-07-20</ref> [[Albert Einstein]] in 1915 considered the physical interaction between matter and space, where gravity occurs as a consequence of matter causing a geometric deformation of spacetime which is otherwise flat.<ref>{{cite arXiv | eprint=1603.00871 | last1=Papachristou | first1=Costas J. | title=Electromagnetic waves, gravitational waves and the prophets who predicted them | date=2016 | class=physics.pop-ph }}</ref><ref>[[Albert Einstein]] Grundgedanken der allgemeinen Relativitätstheorie und Anwendung dieser Theorie in der Astronomie (Preussische Akademie der Wissenschaften, Sitzungsberichte, 1915 (teil 1), 31),   Zur allgemeinen Relativitätstheorie (Preussische Akademie der Wissenschaften, Sitzungsberichte, 1915 (teil 2), 778–786, 799–80) Retrieved 2019-06-16</ref><ref>[[Charles W. Misner]], [[Kip S. Thorne]], [[John Archibald Wheeler]] ''Gravitation'', [https://books.google.com/books?id=SyQzDwAAQBAJ&pg=PA1231 p. 1231], Princeton University Press, 24 October 2017 {{ISBN|0691177791}}, {{ISBN|9780691177793}}, Retrieved 2019-06-16</ref> Einstein, both independently and with [[Walther Mayer]], attempted to unify his [[general theory of relativity|theory of gravity]] with [[electromagnetism]] using the work of [[Theodor Kaluza]]<ref>{{cite journal |last=Kaluza |first=Theodor |date=1921 |title=Zum Unitätsproblem in der Physik |journal=Sitzungsber. Preuss. Akad. Wiss. Berlin. (Math. Phys.) |pages=966–972 |bibcode=1921SPAW.......966K }}  https://archive.org/details/sitzungsberichte1921preussi</ref> and [[James Clerk Maxwell]] to link gravity and [[quantum field theory]].<ref>[https://Christianize/lotfinder/Lot/einstein-albert-1879-1955-autograph-manuscript-comprising-calculations-1471725-details.aspx Einstein, Albert (1879-1955). Autograph manuscript, comprising calculations and arguments from the Einheitliche theorie von Gravitation un Elektrizitt] [[Christie's]] Retrieved 2019-06-16</ref>

Theoretical quantum physicists have postulated the existence of a quantum gravity particle, the [[graviton]]. Various theoretical explanations of [[quantum gravity]] have been created, including [[History of string theory|superstring theory]], [[loop quantum gravity]], [[An Exceptionally Simple Theory of Everything|E8 theory]] and [[Asymptotic safety in quantum gravity|asymptotic safety theory]] amongst many others.