Sonic analogue of black holes and the effects of high frequencies on black hole evaporation

The naive calculation of black hole evaporation makes the thermal emission depend on the arbitrary high frequency behavior of the theory where the theory is certainly wrong. Using the sonic analogue to black holes, ‘‘dumb holes,’’ I show numerically that a change in the dispersion relation at high frequencies does not seem to alter the evaporation process, lending weight to the reality of the black hole evaporation process. I also suggest a reason for the insensitivity of the process to the high frequency regime.