{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T22:11:02Z","timestamp":1760220662560,"version":"build-2065373602"},"reference-count":32,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2012,5,4]],"date-time":"2012-05-04T00:00:00Z","timestamp":1336089600000},"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 modified theories of gravity including a critical acceleration scale a0, a critical length scale rM = (GM\/a0)1\/2 will naturally arise with the transition from the Newtonian to the dark matter mimicking regime occurring for systems larger than rM. This adds a second critical scale to gravity, in addition to the one introduced by the criterion v &lt; c of the Schwarzschild radius, rS = 2GM\/c2. The distinct dependencies of the two above length scales give rise to non-trivial phenomenology in the (mass, length) plane for astrophysical structures, which we explore here. Surprisingly, extrapolation to atomic scales suggests gravity should be at the dark matter mimicking regime there.<\/jats:p>","DOI":"10.3390\/e14050848","type":"journal-article","created":{"date-parts":[[2012,5,4]],"date-time":"2012-05-04T16:09:10Z","timestamp":1336147750000},"page":"848-855","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["A Phase Space Diagram for Gravity"],"prefix":"10.3390","volume":"14","author":[{"given":"Xavier","family":"Hernandez","sequence":"first","affiliation":[{"name":"Instituto de Astronom\u00eda, Universidad Nacional \u00f3noma de M\u00e9xico, AP 70-264, Distrito Federal 04510, M\u00e9xico"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2012,5,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"365","DOI":"10.1086\/161130","article-title":"A modification of the Newtonian dynamics as a possible alternative to the hidden mass hypothesis","volume":"270","author":"Milgrom","year":"1983","journal-title":"Astrophys. 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