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arXiv · 2108.10537

Gradient Flow Structure of a Multidimensional Nonlinear Sixth Order Quantum-Diffusion Equation

Daniel Matthes·Eva-Maria Rott
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Abstract

A nonlinear parabolic equation of sixth order is analyzed. The equation arises as a reduction of a model from quantum statistical mechanics, and also as the gradient flow of a second-order information functional with respect to the $L^2$-Wasserstein metric. First, we prove global existence of weak solutions for initial conditions of finite entropy by means of the time-discrete minimizing movement scheme. Second, we calculate the linearization of the dynamics around the unique stationary solution, for which we can explicitly compute the entire spectrum. A key element in our approach is a particular relation between the entropy, the Fisher information and the second order functional that generates the gradient flow under consideration.

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Daniel Matthes, Eva-Maria Rott. 2021-08-24. Gradient Flow Structure of a Multidimensional Nonlinear Sixth Order Quantum-Diffusion Equation. https://arxiv.org/abs/2108.10537

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