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Relativistic Acoustic Geometry

Neven Bilic
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Abstract

Sound wave propagation in a relativistic perfect fluid with a non-homogeneous isentropic flow is studied in terms of acoustic geometry. The sound wave equation turns out to be equivalent to the equation of motion for a massless scalar field propagating in a curved space-time geometry. The geometry is described by the acoustic metric tensor that depends locally on the equation of state and the four-velocity of the fluid. For a relativistic supersonic flow in curved space-time the ergosphere and acoustic horizon may be defined in a way analogous the non-relativistic case. A general-relativistic expression for the acoustic analog of surface gravity has been found.

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Neven Bilic. 1999-07-31. Relativistic Acoustic Geometry. https://doi.org/10.1088/0264-9381%2F16%2F12%2F312

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