# Tag Info

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Yes, Einstein knew about the Michelson-Morley experiment. Toward the end of his life, he saw it as increasingly important for relativity theory. Here's an excerpt from Clark, Ronald. 1971. Einstein: life and times. New York: World Pub. Co. p. 78: As Einstein said years later, talking to Sir Herbert Samuel in the grounds of Government House, Jerusalem:...

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As far as I know, Einstein was the first to consider a system of massive Bose particles and describe their condensation. I remember reading the relevant paper, but it will take me some time to find the reference. EDIT (6/22/2016): I guess the paper is Sitzungsberichte der Preussischen Akademie der Wissenschaften (1924), 261

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Fizeau in his paper page 92 wrote the following (rough translation) with regard to his experimental set up: The first telescope was placed in the belvedere of a house [an architectural structure sited to take advantage of a scenic view] in Suresnes , the second on the hill of Montmartre, a distance of approximately 8633 meters The disc with seven hundred ...

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I would like to answer with the words of L.D. Landau, from his book Statistical Physics (first edition $1958$):

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Thermodynamics says that entropy increases in a closed system. The Steady State Theory claimed that the universe was not closed. In 1929 Hubble showed that the universe is expanding. To explain how an expanding universe can be Steady State, they claimed that new matter was created continuously to keep the density constant. This new matter would have very ...

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I like the Darigol book that you mention. There is also Uriel Frisch, on Turbulence: The Legacy of Kolomogorov.

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To maintain lepton number as a conserved quantity. Consider, in detail, what's going on in a beta decay (well, I'm going to ignore the nuclear context). The reaction is then $$n \longrightarrow p^+ + e^- + \nu \,,$$ where you should take the symbol $\nu$ to mean some neutrino (without prejudice about matter-type or anti-matter-type for the moment). There ...

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There is something famously called "Feynman's famous formula", which comes up in QFT calculations, which I imagine must be the second FFF referred to in Welton's account. It reads: $$\frac1{a_1 a_2 \ldots a_n} = \int_{x \in \Delta^{n-1}} \frac1{(\sum_{i=1}^n a_i x_i)^n} d\sigma$$ where $\Delta^{n-1}$ denotes the simplex \$\{x = (x_1, \ldots, x_n) \in \...

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The earliest reference I've been able to find on the half-life of 235U is in The Uranium Half-Lives: A Critical Review, by Norman Holden, which reviews various early studies of each of the common isotopes of uranium (232U, 233U, 234U, 235U, 236U, and 238U). The earliest study he cites is Nier (1939) (A. 0. Nier, The isotopic constitution of uranium and the ...

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