Bound on the speed of sound from holography

Journal Article · Tue Sep 15 00:00:00 EDT 2009 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.80.066003· OSTI ID:21322795

Cherman, Aleksey; Cohen, Thomas D; Nellore, Abhinav ^[1]

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1. Center for Fundamental Physics, Department of Physics, University of Maryland, College Park, Maryland 20742-4111 (United States)

We show that the squared speed of sound v{sub s}{sup 2} is bounded from above at high temperatures by the conformal value of 1/3 in a class of strongly coupled four-dimensional field theories, given some mild technical assumptions. This class consists of field theories that have gravity duals sourced by a single-scalar field. There are no known examples to date of field theories with gravity duals for which v{sub s}{sup 2} exceeds 1/3 in energetically favored configurations. We conjecture that v{sub s}{sup 2}=1/3 represents an upper bound for a broad class of four-dimensional theories.

• OSTI ID: 21322795
• Journal Information: Physical Review. D, Particles Fields, Vol. 80, Issue 6; Other Information: DOI: 10.1103/PhysRevD.80.066003; (c) 2009 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CONFIGURATION
FIELD THEORIES
FOUR-DIMENSIONAL CALCULATIONS
GRAVITATION
HOLOGRAPHY
SCALAR FIELDS
SOUND WAVES
STRONG-COUPLING MODEL
TEMPERATURE DEPENDENCE
VELOCITY