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arXiv · 2503.07569

Degenerate parabolic equations in divergence form: fundamental solution and Gaussian bounds

Khalid Baadi
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Abstract

In this paper, we consider second order degenerate parabolic equations with complex, measurable, and time-dependent coefficients. The degenerate ellipticity is dictated by a spatial $A_2$-weight. We prove that having a generalized fundamental solution with upper Gaussian bounds is equivalent to Moser's $L^2$-$L^\infty$ estimates for local weak solutions. In the special case of real coefficients, Moser's $L^2$-$L^\infty$ estimates are known, which provide an easier proof of Gaussian upper bounds, and a known Harnack inequality is then used to derive Gaussian lower bounds.

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Khalid Baadi. 2025-03-10. Degenerate parabolic equations in divergence form: fundamental solution and Gaussian bounds. https://doi.org/10.1007/s00028-026-01201-1

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