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arXiv · 2208.14791

Regularity theory for fully nonlinear parabolic obstacle problems

Alessandro Audrito·Teo Kukuljan
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Abstract

We study the free boundary of solutions to the parabolic obstacle problem with fully nonlinear diffusion. We show that the free boundary splits into a regular and a singular part: near regular points the free boundary is $C^\infty$ in space and time. Furthermore, we prove that the set of singular points is locally covered by a Lipschitz manifold of dimension $n-1$ which is also $\varepsilon$-flat in space, for any $\varepsilon>0$.

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Alessandro Audrito, Teo Kukuljan. 2022-08-31. Regularity theory for fully nonlinear parabolic obstacle problems. https://arxiv.org/abs/2208.14791

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