{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,5]],"date-time":"2026-03-05T14:25:58Z","timestamp":1772720758808,"version":"3.50.1"},"reference-count":44,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2022,2,1]],"date-time":"2022-02-01T00:00:00Z","timestamp":1643673600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>General Relativity allows for a cosmological constant (\u039b) which has inspired models of cosmic Inflation and Dark Energy. We show instead that r\u039b=3\/\u039b corresponds to an event horizon: a causal boundary term in the action. Our Universe is expanding inside its Schwarzschild radius rS=r\u039b=2GM, which could have originated from a uniform free falling cloud of mass M that collapsed as a Black Hole (BH) 25 Gyrs ago. Such a BH Universe allows for large-scale structure formation without the need of Inflation or Dark Energy.<\/jats:p>","DOI":"10.3390\/sym14020300","type":"journal-article","created":{"date-parts":[[2022,2,1]],"date-time":"2022-02-01T22:16:18Z","timestamp":1643753778000},"page":"300","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["The Cosmological Constant as Event Horizon"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9632-0815","authenticated-orcid":false,"given":"Enrique","family":"Gaztanaga","sequence":"first","affiliation":[{"name":"Institute of Space Sciences (ICE, CSIC), 08193 Barcelona, Spain"},{"name":"Institut d Estudis Espacials de Catalunya (IEEC), 08034 Barcelona, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2022,2,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1103\/RevModPhys.61.1","article-title":"The cosmological constant problem","volume":"61","author":"Weinberg","year":"1989","journal-title":"Rev. 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