{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,25]],"date-time":"2026-03-25T11:16:41Z","timestamp":1774437401005,"version":"3.50.1"},"reference-count":28,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2008,7,30]],"date-time":"2008-07-30T00:00:00Z","timestamp":1217376000000},"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>Landauer\u2019s principle is applied to information in the universe. Once stars began forming there was a constant information energy density as the increasing proportion of matter at high stellar temperatures exactly compensated for the expanding universe. The information equation of state was close to the dark energy value, w = -1, for a wide range of redshifts, 10 &gt; z &gt; 0.8, over one half of cosmic time. A reasonable universe information bit content of only 1087 bits is sufficient for information energy to account for all dark energy. A time varying equation of state with a direct link between dark energy and matter, and linked to star formation in particular, is clearly relevant to the cosmic coincidence problem. In answering the \u2018Why now?\u2019 question we wonder \u2018What next?\u2019 as we expect the information equation of state to tend towards w = 0 in the future.c<\/jats:p>","DOI":"10.3390\/entropy-e10030150","type":"journal-article","created":{"date-parts":[[2008,7,30]],"date-time":"2008-07-30T04:31:41Z","timestamp":1217392301000},"page":"150-159","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":19,"title":["Information Equation of State"],"prefix":"10.3390","volume":"10","author":[{"given":"M. Paul","family":"Gough","sequence":"first","affiliation":[{"name":"Space Science Centre, University of Sussex, Brighton, BN1 9QT, United Kingdom"}]}],"member":"1968","published-online":{"date-parts":[[2008,7,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"183","DOI":"10.1147\/rd.53.0183","article-title":"Irreversibility and Heat Generation in the Computing Process","volume":"3","author":"Landauer","year":"1961","journal-title":"IBM J. Res. Dev."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"525","DOI":"10.1147\/rd.176.0525","article-title":"Logical Reversibility of Computation","volume":"17","author":"Bennett","year":"1973","journal-title":"IBM J. Res. Dev."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"905","DOI":"10.1007\/BF02084158","article-title":"The Thermodynamics of Computation \u2013 a Review","volume":"21","author":"Bennett","year":"1982","journal-title":"Int. J. Theor. 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