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Dr. Albert Einstein: Theoretical Physics, Relativity and the Photoelectric Effect, 1935

A Matter of Principle

In 1905, Einstein wrote a paper entitled, "On the Electrodynamics of Moving Bodies." This paper served as the foundation for his theory of relativity. It also included many of the theories and results of scientists whose work had preceded Einstein, so much so that many of his contemporaries had a difficult time distinguishing Einstein's "theory of special relativity" from other accepted theories of the time. The main difference between Einstein's theories and other prevalent scientific theories of the 1900s lies in how Einstein went about deriving his theories. While many of his contemporaries drew "constructive theories," Einstein drew "principle theories."

Einstein's theories were not hypotheses built on data reached through experimentation. Rather, they were universal principles intended to impact all of physics. Throughout his life, Einstein was driven by a desire to isolate a single theory that would unify gravitation and electromagnetic fields. Though this single theory has not yet been found, Einstein's work has inspired physicists of today to continue the search for a unified theory.