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arXiv · 2601.01035

Irregular Diffusions and Loss of Regularity in Polyconvex Gradient Flows

Bin Guo·Seonghak Kim·Baisheng Yan
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Abstract

We investigate diffusion-type partial differential equations that are irregular in the sense that they admit weak solutions which are nowhere smooth, even for prescribed smooth data. By reformulating these equations as first-order partial differential relations and adapting the method of convex integration, we develop a construction scheme based on new geometric structures, referred to as $\mathcal{T}_N$-configurations, together with a simplified structural hypothesis on the diffusion functions, termed Condition $O_N$. Under this condition, we show that the associated initial and boundary value problems with certain smooth initial-boundary data admit infinitely many Lipschitz weak solutions that are nowhere $C^1$. We further analyze specific $\mathcal{T}_N$-configurations and establish nondegeneracy conditions that are essential for verifying Condition $O_N$. As an application, we construct examples of strongly polyconvex energy functionals whose gradient flows generate irregular diffusion equations, thereby revealing a failure of regularity and uniqueness even within the class of polyconvex gradient flows.

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Bin Guo, Seonghak Kim, Baisheng Yan. 2026-01-03. Irregular Diffusions and Loss of Regularity in Polyconvex Gradient Flows. https://arxiv.org/abs/2601.01035

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