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arXiv · 2402.16805

A parabolic free transmission problem: flat free boundaries are smooth

Dennis Kriventsov·María Soria-Carro
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Abstract

We study a two-phase parabolic free boundary problem motivated by the jump of conductivity in composite materials that undergo a phase transition. Each phase is governed by a heat equation with distinct thermal conductivity, and a transmission-type condition is imposed on the free interface. We establish strong regularity properties of the free boundary: first, we prove that flat free boundaries are $C^{1,\alpha}$ by means of a linearization technique and compactness arguments. Then we use the Hodograph transform to achieve higher regularity. To this end, we prove a new Harnack-type inequality and develop the Schauder theory for parabolic linear transmission problems.

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Dennis Kriventsov, María Soria-Carro. 2024-02-26. A parabolic free transmission problem: flat free boundaries are smooth. https://arxiv.org/abs/2402.16805

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