Firewall argument for acoustic black holes
Pontiggia, Luca Terzio
We investigate the rewall paradox proposed by AMPS  by rst explaining the Information Paradox together with Hawking's derivation of the thermal radiation emitted from a evaporating black hole . We then ask if one can apply arguments similar to that of Hawking and AMPS in the regime of uid mechanics, which was rst considered by Unruh . We assume that a black hole, with a geometry conformal to the Schwarzschild metric, can be formed in a uid. The sonic hole or \dumb" hole, which is characterized by an acoustic event horizon, is the locus of points at which the background uid is traveling at the local speed of sound. Since sound disturbances are coupled to the background uid and travel at the speed of sound, the acoustic event horizon a ects sound disturbances in a manner analogous to how gravitational black holes a ect light . Like a gravitational black hole, which evaporates by emitting Hawking radiation, we check if an acoustic black hole will emit in a similar kind of radiation in the form of phonons. This is done by constructing a massless scalar eld describing phonon propagation and treating the acoustic black hole just like a gravitational black hole. We apply the arguments put forth by Hawking and AMPS and see if there is any validity to an \acoustic rewall" as this would require certain physical phenomena emerging from sub-atomic scales.
A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of requirements for the degree of Master of Science. June 8, 2015.