Lot 399

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Einstein on “theory of relativity” and “speed of light”, One of the Best in English Available on the Subject, with Additional Archive

ALBERT EINSTEIN. Typed Letter Signed, "A. Einstein", 1p, on "The Institute for Advanced Study" letterhead, 8.5" x 11", Princeton, April 4, 1951. One word, “local”, is underlined by Einstein. Letter has expected mailing folds, toning, light wear and a very short tear at right margin. Includes original envelope.

In this fascinating letter, Einstein writes that, “According to the special theory of relativity the velocity of light relatively to an inertial system is something clearly defined and this speed of light is a limit for the speed of any object.” In the general theory, he explains, the picture is more complex, “there is still the well-defined velocity of light with respect to a local coordinate system”, but the theory does not allow for any “privileged” coordinate systems “so that it makes no sense in general to speak about the speed of light with respect to the coordinate system.” Einstein goes on to consider “special cases where natural choice of the coordinate system exists” which would allow for discussion of the velocity of light, which would, however, no longer be a constant, “but something which depends from the coordinates...from time.”

The recipient of this letter, Sam Moskowitz, was a science fiction writer and historian of science fiction. Moskowitz wrote to Einstein to clarify “a vital point in the writing of science fiction". He observed that “one of the biggest obstacles science fiction writers have has to overcome in carrying their characters to the far galaxies is the general acceptance of the idea that a material object cannot exceed the speed of light”. Noting that in a recent paper, English astronomer Fred Hoyle had said that the general theory of relativity allows such a possibility, Moskowitz asked Einstein for clarification.

Einstein’s letter is accompanied by a carbon copy of Moskowitz's letter to Einstein dated March 28, 1951, and a 3pp letter by English astronomer Fred Hoyle to Moskowitz, explaining Einstein's letter.

This item comes with a Certificate from John Reznikoff, a premier authenticator for both major 3rd party authentication services, PSA and JSA (James Spence Authentications), as well as numerous auction houses.


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May 4, 2022 10:30 AM EDT
Wilton, CT, US

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