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Dumb Holes and the Effects of High Frequencies on Black Hole Evaporation

W. G. Unruh
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Abstract

The naive calculation of black hole evaporation makes the thermal emission depend on the arbitrary high frequency behaviour of the theory where the theory is certainly wrong. Using the sonic analog 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 high frequency regime.

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W. G. Unruh. 1999-10-18. Dumb Holes and the Effects of High Frequencies on Black Hole Evaporation. https://doi.org/10.1103/physrevd.51.2827

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