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https://en.wikipedia.org/wiki/Heligoland

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Werner Heisenberg (1901–1976) first formulated the equation underlying his picture of quantum mechanics while on Heligoland in the 1920s. While a student of Arnold Sommerfeld at Munich in the early 1920s, Heisenberg first met the Danish physicist Niels Bohr. He and Bohr went for long hikes in the mountains and discussed the failure of existing theories to account for the new experimental results on the quantum structure of matter. Following these discussions, Heisenberg plunged into several months of intensive theoretical research but met with continual frustration. Finally, suffering from a severe attack of hay fever, he retreated to the treeless (and pollenless) island of Heligoland in the summer of 1925. There he conceived the basis of the quantum theory.
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https://plato.stanford.edu/entries/russell-paradox/

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John von Neumann’s (1925) untyped method for dealing with paradoxes, and with Russell’s paradox in particular, is simple and ingenious. Von Neumann introduces a distinction between membership and non-membership and, on this basis, draws a distinction between sets and classes. An object is a member (simpliciter) if it is a member of some class; and it is a non-member if it is not a member of any class.
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https://en.wikipedia.org/wiki/Russell%27s_paradox

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Informal presentation Most sets commonly encountered are not members of themselves. For example, consider the set of all squares in the plane. This set is not itself a square in the plane, thus it is not a member of itself. Let us call a set “normal” if it is not a member of itself, and “abnormal” if it is a member of itself. Clearly every set must be either normal or abnormal. The set of squares in the plane is normal. In contrast, the complementary set that contains everything which is not a square in the plane is itself not a square in the plane, and so it is one of its own members and is therefore abnormal. Now we consider the set of all normal sets, R, and try to determine whether R is normal or abnormal. If R were normal, it would be contained in the set of all normal sets (itself), and therefore be abnormal; on the other hand if R were abnormal, it would not be contained in the set of all normal sets (itself), and therefore be normal. This leads to the conclusion that R is neither normal nor abnormal: Russell’s paradox.
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https://en.wikipedia.org/wiki/History_of_numerical_weather_prediction
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In 1922, Lewis Fry Richardson published the first attempt at forecasting the weather numerically. Using a hydrostatic variation of Bjerknes’s primitive equations,[2] Richardson produced by hand a 6-hour forecast for the state of the atmosphere over two points in central Europe, taking at least six weeks to do so.[3] His forecast calculated that the change in surface pressure would be 145 millibars (4.3 inHg), an unrealistic value incorrect by two orders of magnitude. The large error was caused by an imbalance in the pressure and wind velocity fields used as the initial conditions in his analysis.[2] The first successful numerical prediction was performed using the ENIAC digital computer in 1950 by a team led by American meteorologist Jule Charney. The team include Philip Thompson, Larry Gates, and Norwegian meteorologist Ragnar Fjørtoft, applied mathematician John von Neumann, and computer programmer Klara Dan von Neumann, M. H. Frankel, Jerome Namias, John C. Freeman Jr., Francis Reichelderfer, George Platzman, and Joseph Smagorinsky.[5][6][7] They used a simplified form of atmospheric dynamics based on solving the barotropic vorticity equation over a single layer of the atmosphere, by computing the geopotential height of the atmosphere’s 500 millibars (15 inHg) pressure surface.[8] This simplification greatly reduced demands on computer time and memory, so the computations could be performed on the relatively primitive computers of the day.[9] When news of the first weather forecast by ENIAC was received by Richardson in 1950, he remarked that the results were an “enormous scientific advance.”[2] The first calculations for a 24‑hour forecast took ENIAC nearly 24 hours to produce,[2] but Charney’s group noted that most of that time was spent in “manual operations”, and expressed hope that forecasts of the weather before it occurs would soon be realized.[8]
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