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arXiv · 2106.13363

Hardy's inequality and (almost) the Landau equation

Maria Gualdani·Nestor Guillen
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Abstract

In this manuscript we establish an $L^\infty$ estimate for the isotropic analogue of the homogeneous Landau equation. This is done for values of the interaction exponent $\gamma$ in (a part of) the range of very soft potentials. The main observation in our proof is that the classical weighted Hardy inequality leads to a weighted Poincar\'e inequality, which in turn implies the propagation of some $L^p$ norms of solutions. From here, the $L^\infty$ estimate follows from certain weighted Sobolev inequalities and De Giorgi-Nash-Moser theory.

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Maria Gualdani, Nestor Guillen. 2021-06-25. Hardy's inequality and (almost) the Landau equation. https://arxiv.org/abs/2106.13363

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