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arXiv · 2604.11134

Oscillating solutions to the mean-field Langevin descent-ascent flow

Jean-Christophe Mourrat·Loucas Pillaud-Vivien
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Abstract

We present a counterexample to the statement of convergence of the mean-field Langevin descent-ascent flow on $\mathbb{R}^2$. We consider payoff functions that are shaped as a double well in each coordinate, and for which the deterministic dynamics admits a limit cycle. When the coupling between the two coordinates is sufficiently strong and the entropic regularization sufficiently small, we show that the mean-field dynamics remains close to this cyclic behavior, and in particular, does not converge.

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Jean-Christophe Mourrat, Loucas Pillaud-Vivien. 2026-04-13. Oscillating solutions to the mean-field Langevin descent-ascent flow. https://arxiv.org/abs/2604.11134

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