Theory of relativity Albert Einstein's theory of relativity is a set of two theories in physics: special relativity and general relativity. The core idea of both theories is that two observers who move relative to each other will often measure different time and space intervals for the same events, but the content of physical law will be the same for both. Special relativity, developed in 1905, considers that observers in inertial reference frames which are in uniform motion relative to one another cannot perform any experiment to determine which one of them is in "absolute motion". Einstein's paper that year was called "On the Electrodynamics of Moving Bodies". While developing this theory, Einstein wrote to his wife Mileva about "our work on relative motion". This paper introduced the special theory of relativity, a theory of time, distance, mass and energy. The theory postulates that the speed of light in vacuum will be the same for these observers (i.e. an observer invariant speed). One of the strengths of special relativity is that it can be derived from only a few premises: The speed of light in vacuum is a constant. The laws of physics are the same for all observers in inertial frames. General relativity was published by Einstein in 1916 (submitted as a series of lectures before the Prussian Academy of Sciences November 25 1915). However, it must be noted that German mathematician David Hilbert wrote and made public the covariant equations before Einstein. This resulted in not a few accusations of plagiarism against Einstein, but it is probably closer to reality that they both were co-creators of general relativity. The theory gave an introduction of an equation that replaced Newton's law of gravity. It uses the mathematics of differential geometry and tensors in order to describe gravity. This theory considered all observers to be equivalent, not only those moving at a uniform speed. The laws of general relativity are the same for all observers, even if they are accelerated with respect to each other. In general relativity, gravity is no longer a force (as it was in Newton's law of gravity) but is a consequence of the curvature of space-time. General relativity is a geometrical theory which postulates that the presence of mass and energy "curves" spacetime, and this curvature affects the path of free particles (and even the path of light). For more information see the respective articles on special relativity and general relativity. See also List of publications in physics: Theory of relativity External links Probe set to test theory of Relativity Living Reviews in Relativity — An open access, peer-refereed, solely online physics journal publishing invited reviews covering all areas of relativity research. Reflections on Relativity — A complete online course on Relativity. Relativity explained in words of four letters or less Briefing on Einstein's Theory of Relativity — A terse dose of insight on the subject. http://tprints.ecs.soton.ac.uk/40/01/Macroscopic_Spacetime_Shortcuts.pdfEvaluation of Manyfold spacetime short cuts from Relativity. Did Einstein cheat? FAVORITE ARTICLES: History of the World    History of the United States    History of Europe    Ancient History    History    Military History    World War I    Bombing of Dresden    California    US Constitution    Frank Sinatra    Boston    Marbury v. Madison This article is licensed under the GNU Free Documentation License at http://www.gnu.org/copyleft/fdl.html You may copy and modify it as long as the entire work (including additions) remains under this license. You must provide a link to http://www.gnu.org/copyleft/fdl.html To view or edit this article at Wikipedia go to http://www.wikipedia.org/wiki/Theory_of_relativity">follow this link. All other content is copyright © 2000-2005 by WorldHistory.com. All rights reserved.

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