How Unsatisfactory Is the Postulation of Low Entropy in the Early Universe?
DOI:
https://doi.org/10.35588/cc.v7d8361Keywords:
Past Hypothesis, entropy, second lawAbstract
This article examines the Past Hypothesis (PH), understood as the postulate that the universe began in an initial state of extremely low entropy, a condition usually regarded as necessary to ground the statistical explanation of the second law of thermodynamics. It is argued that, although the PH plays a formal role in the statistical explanation of the second law, its mere postulation carries a significant epistemic cost, since it introduces as an initial condition precisely a state that the statistical framework itself characterizes as extraordinarily atypical. Without an adequate explanation of this condition, the scientific worldview remains incomplete, since a satisfactory grounding of the second law would remain pending, together with an account of the arrow of time and the irreversibility of physical processes.
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2026-10-31Published
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Copyright (c) 2026 Aldo Filomeno, José Ignacio Jerez Torrens
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