Determination of the Spectral Gap for Kac’s Master Equation and Related Stochastic Evolutions
نویسندگان
چکیده
We present a method for bounding, and in some cases computing, the spectral gap for systems of many particles evolving under the influence a random collision mechanism. In particular, the method yields the exact spectral gap in a model due to Mark Kac of energy conserving collisions with one dimensional velocities. It is also sufficiently robust to provide qualitatively sharp bounds also in the case of more physically realistic momentum and energy conserving conserving collisions in three dimensions, as well as a range of related models.
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