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medium-entropy state would have likely evolved both from and toward higher-entropy macrostates, as there are more ways statistically to be high-entropy than low-entropy. The low- or medium-entropy state would have appeared as a "statistical fluctuation" amid a higher-entropy past and a higher-entropy future.
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would have an equal probability. The past hypothesis allows only those microstates that are compatible with a much-lower-entropy past, although these states are assigned equal probabilities. If the principle of indifference is applied without taking into account the past hypothesis, a low- or
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in 2000. Philosophical and theoretical efforts focus on trying to explain the consistency and the origin of the postulate.
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Common theoretical frameworks have been developed in order to explain the origin of the past hypothesis based on
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R., Penrose (1979). "Singularities and time-asymmetry". In S. W. Hawking; W. Israel (eds.).
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This idea has been discussed since the development of
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that postulates that the universe started in a low-
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185:"Cosmic inflation and the past hypothesis"
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