Peer-Reviewed Journal Details
Mandatory Fields
Dolan B.
2011
December
Physical Review D - Particles, Fields, Gravitation and Cosmology
Compressibility of rotating black holes
Published
()
Optional Fields
84
12
Interpreting the cosmological constant as a pressure, whose thermodynamically conjugate variable is a volume, modifies the first law of black hole thermodynamics. Properties of the resulting thermodynamic volume are investigated: the compressibility and the speed of sound of the black hole are derived in the case of nonpositive cosmological constant. The adiabatic compressibility vanishes for a nonrotating black hole and is maximal in the extremal case-comparable with, but still less than, that of a cold neutron star. A speed of sound v s is associated with the adiabatic compressibility, which is equal to c for a nonrotating black hole and decreases as the angular momentum is increased. An extremal black hole has vs2=0.9c2 when the cosmological constant vanishes, and more generally v s is bounded below by c/√2. © 2011 American Physical Society.
1550-7998
10.1103/PhysRevD.84.127503
Grant Details