TY - JOUR

T1 - A larger estimate of the entropy of the universe

AU - Egan, Chas A.

AU - Lineweaver, Charles H.

PY - 2010

Y1 - 2010

N2 - 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 Sobs = 3.1+3.0 -1.7 × 10104 k. We calculate the entropy of the current cosmic event horizon to be SCEH = 2.6±0.3 × 10122 k, dwarfing the entropy of its interior, SCEH int = 1.2+1.1-0.7 × 10103k. We make the first tentative estimate of the entropy of weakly interacting massive particle dark matter within the observable universe, Sdm = 1088±1 k. We highlight several caveats pertaining to these estimates and make recommendations for future work.

AB - 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 Sobs = 3.1+3.0 -1.7 × 10104 k. We calculate the entropy of the current cosmic event horizon to be SCEH = 2.6±0.3 × 10122 k, dwarfing the entropy of its interior, SCEH int = 1.2+1.1-0.7 × 10103k. We make the first tentative estimate of the entropy of weakly interacting massive particle dark matter within the observable universe, Sdm = 1088±1 k. We highlight several caveats pertaining to these estimates and make recommendations for future work.

KW - Black hole physics

KW - Cosmology: miscellaneous

KW - Diffusion

KW - Elementary particles

KW - Gravitation

KW - Neutrinos

UR - http://www.scopus.com/inward/record.url?scp=77149171447&partnerID=8YFLogxK

U2 - 10.1088/0004-637X/710/2/1825

DO - 10.1088/0004-637X/710/2/1825

M3 - Article

SN - 0004-637X

VL - 710

SP - 1825

EP - 1834

JO - Astrophysical Journal

JF - Astrophysical Journal

IS - 2

ER -