{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T22:14:12Z","timestamp":1760220852687,"version":"build-2065373602"},"reference-count":76,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2013,9,26]],"date-time":"2013-09-26T00:00:00Z","timestamp":1380153600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>In a previous paper, we introduced a way to generate a time coordinate system for classical and quantum systems when the potential function has extremal points. In this paper, we deal with the case in which the potential function has no extremal points at all, and we illustrate the method with the harmonic and linear potentials.<\/jats:p>","DOI":"10.3390\/e15104105","type":"journal-article","created":{"date-parts":[[2013,9,26]],"date-time":"2013-09-26T12:48:59Z","timestamp":1380199739000},"page":"4105-4121","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Time Eigenstates for Potential Functions without Extremal Points"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3122-0546","authenticated-orcid":false,"given":"Gabino","family":"Torres-Vega","sequence":"first","affiliation":[{"name":"Physics Department, Cinvestav, Apdo. postal 14-740, M\u00e9xico D.F. 07300, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2013,9,26]]},"reference":[{"key":"ref_1","unstructured":"Holevo, A.S. 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