Mean value formulas for classical solutions to uniformly parabolic equations in divergence form

Emanuele Malagoli; Diego Pallara; Sergio Polidoro

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arXiv · 2109.00934

Mean value formulas for classical solutions to uniformly parabolic equations in divergence form

Emanuele Malagoli·Diego Pallara·Sergio Polidoro

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Abstract

We prove surface and volume mean value formulas for classical solutions to uniformly parabolic equations in divergence form. We then use them to prove the parabolic strong maximum principle and the parabolic Harnack inequality. We emphasize that our results only rely on the classical theory, and our arguments follow the lines used in the original theory of harmonic functions. We provide two proofs relying on two different formulations of the divergence theorem, one stated for sets with almost C^1 boundary, the other stated for sets with finite perimeter.

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Emanuele Malagoli, Diego Pallara, Sergio Polidoro. 2021-09-02. Mean value formulas for classical solutions to uniformly parabolic equations in divergence form. https://arxiv.org/abs/2109.00934

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