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What is Einstein's Theory of Relativity? - Universe Today
There are two, theories of relativity, by Einstein, the special theory of relativity (or just special relativity, SR), and the general theory of relativity (or just general relativity, GR). The special theory of relativity was published in 1905, in Annalen der Physik (“Zur Elektrodynamik bewegter Körper“, in the original German; “On the Electrodynamics of Moving … Continue reading "What is Einstein’s Theory of Relativity?"