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arXiv · 0908.2226

Improved intermediate asymptotics for the heat equation

Jean-Philippe Bartier·Adrien Blanchet·Jean Dolbeault·Miguel Escobedo
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Abstract

This letter is devoted to results on intermediate asymptotics for the heat equation. We study the convergence towards a stationary solution in self-similar variables. By assuming the equality of some moments of the initial data and of the stationary solution, we get improved convergence rates using entropy / entropy-production methods. We establish the equivalence of the exponential decay of the entropies with new, improved functional inequalities in restricted classes of functions. This letter is the counterpart in a linear framework of a recent work on fast diffusion equations, see [Bonforte-Dolbeault-Grillo-Vazquez]. Results extend to the case of a Fokker-Planck equation with a general confining potential.

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Jean-Philippe Bartier, Adrien Blanchet, Jean Dolbeault, Miguel Escobedo. 2009-08-16. Improved intermediate asymptotics for the heat equation. https://arxiv.org/abs/0908.2226

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