https://www.britannica.com/biography/John-von-Neumann/Princeton-1930-42
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Never much like the stereotypical mathematician, he was known as a wit, bon vivant, and aggressive driver—his frequent auto accidents led to one Princeton intersection being dubbed “von Neumann corner.” “}}
Posts Tagged ‘jvn0mg’
His corner in Princeton –was– John von Neumann – Princeton, 1930–42 | Britannica
January 1, 2022Lise Meitner – Wikipedia
January 1, 2022https://en.wikipedia.org/wiki/Lise_Meitner
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At that point we both sat down on a tree trunk (all that discussion had taken place while we walked through the wood in the snow, I with my skis on, Lise Meitner making good her claim that she could walk just as fast without), and started to calculate on scraps of paper. The charge of a uranium nucleus, we found, was indeed large enough to overcome the effect of the surface tension almost completely; so the uranium nucleus might indeed resemble a very wobbly unstable drop, ready to divide itself at the slightest provocation, such as the impact of a single neutron. But there was another problem. After separation, the two drops would be driven apart by their mutual electric repulsion and would acquire high speed and hence a very large energy, about 200 MeV in all; where could that energy come from? Fortunately Lise Meitner remembered the empirical formula for computing the masses of nuclei and worked out that the two nuclei formed by the division of a uranium nucleus together would be lighter than the original uranium nucleus by about one-fifth the mass of a proton. Now whenever mass disappears energy is created, according to Einstein’s formula E = mc2, and one-fifth of a proton mass was just equivalent to 200 MeV. So here was the source for that energy; it all fitted![98]
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Nuclear chain reaction – Wikipedia
January 1, 2022Ergodic theory – Wikipedia
December 31, 2021https://en.wikipedia.org/wiki/Ergodic_theory#Mean_ergodic_theorem
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A central concern of ergodic theory is the behavior of a dynamical system when it is allowed to run for a long time. The first result in this direction is the Poincaré recurrence theorem, which claims that almost all points in any subset of the phase space eventually revisit the set. Systems for which the Poincaré recurrence theorem holds are conservative systems; thus all ergodic systems are conservative. More precise information is provided by various ergodic theorems which assert that, under certain conditions, the time average of a function along the trajectories exists almost everywhere and is related to the space average. Two of the most important theorems are those of Birkhoff (1931) and von Neumann which assert the existence of a time average along each trajectory. For the special class of ergodic systems, this time average is the same for almost all initial points: statistically speaking, the system that evolves for a long time “forgets” its initial state. Stronger properties, such as mixing and equidistribution, have also been extensively studied.
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Reinhold Bertlmann – Wikipedia
December 30, 2021https://en.wikipedia.org/wiki/Reinhold_Bertlmann
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In 1978 Bertlmann went to CERN, where he worked together with J. S. Bell.[1] Bertlmann always wore socks of different colours. In 1981 Bell wrote the article “Bertlmann’s socks and the nature of reality”, where he compared the EPR paradox with Bertlmann’s socks: if you observe one sock to be pink you can predict with certainty that the other sock is not pink. Thus you might assume that quantum
entanglement is just the same. However, this is a non-admissible simplification, and Bell in his article explains why.[2]
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