# The ambiguous meaning of irreversibility

Source: [The ambiguous meaning of irreversibility](<https://www.sota2.com/research/paper/68fa21407a2b558e29336086>)

Collection index: [llms.txt](<https://www.sota2.com/research/llms.txt>)

Data updated: 2025-10-24T00:27:40.902Z

Authors: X. de Hemptinne

Published: 1995-02-06T10:14:17.000Z

## Abstract

Irreversibility of spontaneous macroscopic dynamics and its asymmetry with respect to the sign reversal of the variable $t$ is usually interpreted as a genuine property of complex isolated systems. Discussion of the kinetics involved in Joule's experiment concerning spontaneous expansion of a gas shows that the isolation hypothesis results from ambiguous definitions of a number of keywords. Whereas Poincar\\'{e}'s apparent irreversibility result from conservative Hamiltonian dynamics, full relaxation implies interaction with the outside world. Only the latter process leads to entropy change.

## Recorded benchmark results

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## Original sources and implementation

[Original paper](<https://arxiv.org/abs/chao-dyn/9502004>)

[PDF](<https://arxiv.org/pdf/chao-dyn/9502004.pdf>)