A quantitative modulus of continuity for the two-phase Stefan problem

Abstract

We derive the quantitative modulus of continuity $$\omega (r)={\left[p+\ln \left(\frac{r_0}{r}\right)\right]}^{-\alpha (n,p)},$$ which we conjecture to be optimal, for solutions of the $p$-degenerate two-phase Stefan problem. Even in the classical case $p=2$, this represents a twofold improvement with respect to the 1984 state-of-the-art result by DiBenedetto and Friedman [J. reine angew. Math., 1984], in the sense that we discard one logarithm iteration and obtain an explicit value for the exponent $\alpha (n,p)$.

23 pages