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Title: A LARGER ESTIMATE OF THE ENTROPY OF THE UNIVERSE

Journal Article · · Astrophysical Journal
 [1]
  1. Research School of Astronomy and Astrophysics, Australian National University, Canberra (Australia)

Using recent measurements of the supermassive black hole (SMBH) mass function, we find that SMBHs are the largest contributor to the entropy of the observable universe, contributing at least an order of magnitude more entropy than previously estimated. The total entropy of the observable universe is correspondingly higher, and is S{sub obs} = 3.1{sup +3.0}{sub -1.7} x 10{sup 104} k. We calculate the entropy of the current cosmic event horizon to be S{sub CEH} = 2.6 +- 0.3 x 10{sup 122} k, dwarfing the entropy of its interior, S{sub CEH{sub int}} = 1.2{sup +1.1}{sub -0.7} x 10{sup 103} k. We make the first tentative estimate of the entropy of weakly interacting massive particle dark matter within the observable universe, S{sub dm} = 10{sup 88+}-{sup 1} k. We highlight several caveats pertaining to these estimates and make recommendations for future work.

OSTI ID:
21394398
Journal Information:
Astrophysical Journal, Vol. 710, Issue 2; Other Information: DOI: 10.1088/0004-637X/710/2/1825; ISSN 0004-637X
Country of Publication:
United States
Language:
English