{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,18]],"date-time":"2026-05-18T17:27:44Z","timestamp":1779125264269,"version":"3.51.4"},"reference-count":22,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2022,2,23]],"date-time":"2022-02-23T00:00:00Z","timestamp":1645574400000},"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":"<jats:p>I explore the processes of equilibration exhibited by the Adapted Caldeira\u2013Leggett (ACL) model, a small unitary \u201ctoy model\u201d developed for numerical studies of quantum decoherence between an SHO and an environment. I demonstrate how dephasing allows equilibration to occur in a wide variety of situations. While the finite model size and other \u201cunphysical\u201d aspects prevent the notions of temperature and thermalization from being generally applicable, certain primitive aspects of thermalization can be realized for particular parameter values. I link the observed behaviors to intrinsic properties of the global energy eigenstates, and argue that the phenomena I observe contain elements which might be key ingredients that lead to ergodic behavior in larger more realistic systems. The motivations for this work range from curiosity about phenomena observed in earlier calculations with the ACL model to much larger questions related to the nature of equilibrium, thermalization, and the emergence of physical laws.<\/jats:p>","DOI":"10.3390\/e24030316","type":"journal-article","created":{"date-parts":[[2022,2,23]],"date-time":"2022-02-23T09:34:38Z","timestamp":1645608878000},"page":"316","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Equilibration and \u201cThermalization\u201d in the Adapted Caldeira\u2013Leggett Model"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9829-5211","authenticated-orcid":false,"given":"Andreas","family":"Albrecht","sequence":"first","affiliation":[{"name":"Center for Quantum Mathematics and Physics, University of California at Davis, One Shields Ave., Davis, CA 95616, USA"},{"name":"Department of Physics and Astronomy, University of California at Davis, One Shields Ave., Davis, CA 95616, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,2,23]]},"reference":[{"key":"ref_1","unstructured":"Albrecht, A., Baunach, R., and Arrasmith, A. 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