Mathematical Field Notes

Posts Tagged ‘Light

Is the speed of light constant?

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I recently came across a beautiful argument due to De Sitter (1913), which gave the (first?) experimental evidence that light moves with a constant speed.

Constancy of the speed of light is one of those things that always bothered me, and I spent a couple of days recently trying to unbother myself. De Sitter’s argument is what finally satisfied me. Below, I’m going to explain the background, then I’ll explain De Sitter’s argument. The De Sitter paper is only a couple of paragraphs long and is available via Wikisource, so if you don’t need the introductory remarks in the blogpost below, just follow the link above and read it.

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Written by Jonny Evans

August 9, 2016 at 5:33 pm

Posted in Physics

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