{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,5,10]],"date-time":"2025-05-10T10:06:08Z","timestamp":1746871568949},"reference-count":18,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2018,3,28]],"date-time":"2018-03-28T00:00:00Z","timestamp":1522195200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"The second law of thermodynamics states the increase of entropy, \u0394 S > 0 , for real processes from state A to state B at constant energy from chemistry over biological life and engines to cosmic events. The connection of entropy to information, phase-space, and heat is helpful but does not immediately convince observers of the validity and basis of the second law. This gave grounds for finding a rigorous, but more easily acceptable reformulation. Here, we show using statistical mechanics that this principle is equivalent to a force law \u27e8 \u27e8 f \u27e9 \u27e9 > 0 in systems where mass centers and forces can be identified. The sign of this net force--the average mean force along a path from A to B--determines the direction of the process. The force law applies to a wide range of processes from machines to chemical reactions. The explanation of irreversibility by a driving force appears more plausible than the traditional formulation as it emphasizes the cause instead of the effect of motions.<\/jats:p>","DOI":"10.3390\/e20040234","type":"journal-article","created":{"date-parts":[[2018,3,29]],"date-time":"2018-03-29T09:26:37Z","timestamp":1522315597000},"page":"234","source":"Crossref","is-referenced-by-count":2,"title":["The Second Law of Thermodynamics as a Force Law"],"prefix":"10.3390","volume":"20","author":[{"given":"J\u00fcrgen","family":"Schlitter","sequence":"first","affiliation":[{"name":"Biophysics, Ruhr-University Bochum, 44780 Bochum, Germany"}]}],"member":"1968","published-online":{"date-parts":[[2018,3,28]]},"reference":[{"key":"ref_1","first-page":"1","article-title":"\u00dcber verschiedene f\u00fcr die Anwendung bequeme Formen der Hauptgleichungen der mechanischen W\u00e4rmetheorie. 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