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arXiv · 2209.11149

Characterisation of gradient flows for a given functional

Morris Brooks·Jan Maas
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Abstract

Let $X$ be a vector field and $Y$ be a co-vector field on a smooth manifold $M$. Does there exist a smooth Riemannian metric $g_{\alpha \beta}$ on $M$ such that $Y_\beta = g_{\alpha \beta} X^\alpha$? The main result of this note gives necessary and sufficient conditions for this to be true. As an application of this result we show that a finite-dimensional ergodic Lindblad equation admits a gradient flow structure for the von Neumann relative entropy if and only if the condition of BKM-detailed balance holds.

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Morris Brooks, Jan Maas. 2022-09-22. Characterisation of gradient flows for a given functional. https://arxiv.org/abs/2209.11149

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