A New Approach to Velocity Averaging Lemmas in Besov Spaces
نویسنده
چکیده
We develop a new approach to velocity averaging lemmas based on the dispersive properties of the kinetic transport operator. This method yields unprecedented sharp results, which display, in some cases, a gain of one full derivative. Moreover, the study of dispersion allows to treat the case of LxL p v integrability with r ≤ p. We also establish results on the control of concentrations in the degenerate Lx,v case, which is fundamental in the study of the hydrodynamic limit of the Boltzmann equation. CONTENTS
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