Editing Theory of relativity (section)

== Development and acceptance ==
{{Main|History of special relativity|History of general relativity}}
{{General relativity sidebar}}

[[Albert Einstein]] published the theory of [[special relativity]] in 1905, building on many theoretical results and empirical findings obtained by [[Albert A. Michelson]], [[Hendrik Lorentz]], [[Henri Poincaré]] and others. [[Max Planck]], [[Hermann Minkowski]] and others did subsequent work.

Einstein developed [[general relativity]] between 1907 and 1915, with contributions by many others after 1915. The final form of general relativity was published in 1916.<ref name=relativity/>

The term "theory of relativity" was based on the expression "relative theory" ({{langx|de|Relativtheorie}}) used in 1906 by Planck, who emphasized how the theory uses the [[principle of relativity]]. In the discussion section of the same paper, [[Alfred Bucherer]] used for the first time the expression "theory of relativity" ({{langx|de|Relativitätstheorie}}).<ref>{{Citation|author=Planck, Max|date=1906 |title=Die Kaufmannschen Messungen der Ablenkbarkeit der β-Strahlen in ihrer Bedeutung für die Dynamik der Elektronen (The Measurements of Kaufmann on the Deflectability of β-Rays in their Importance for the Dynamics of the Electrons)|journal=Physikalische Zeitschrift|volume=7 |pages=753–761|title-link=s:Translation:The Measurements of Kaufmann }}</ref><ref>{{Citation|last=Miller |first=Arthur I.|date=1981|title=Albert Einstein's special theory of relativity. Emergence (1905) and early interpretation (1905–1911)|location=Reading |publisher=Addison–Wesley|isbn=978-0-201-04679-3}}</ref>

By the 1920s, the physics community understood and accepted special relativity.<ref>{{cite book |title=The New Quantum Universe |edition=illustrated, revised |first1=Anthony J.G. |last1=Hey |first2=Patrick |last2=Walters |publisher=Cambridge University Press |date=2003 |isbn=978-0-521-56457-1 |page=227 |url=https://books.google.com/books?id=cTk-eVzT1oMC&pg=PA227|bibcode=2003nqu..book.....H }}</ref> It rapidly became a significant and necessary tool for theorists and experimentalists in the new fields of [[atomic physics]], [[nuclear physics]], and [[quantum mechanics]].

By comparison, general relativity did not appear to be as useful, beyond making minor corrections to predictions of Newtonian gravitation theory.<ref name="relativity" /> It seemed to offer little potential for experimental test, as most of its assertions were on an astronomical scale. Its [[Tensor analysis|mathematics]] seemed difficult and fully understandable only by a small number of people. Around 1960, general relativity became central to physics and astronomy. New mathematical techniques to apply to general relativity streamlined calculations and made its concepts more easily visualized. As astronomical [[phenomena]] were discovered, such as [[quasars]] (1963), the 3-kelvin [[microwave background radiation]] (1965), [[pulsar]]s (1967), and the first [[black hole]] candidates (1981),<ref name="relativity" /> the theory explained their attributes, and measurement of them further confirmed the theory.