A simplified characterization of stable-like heat kernel estimates

Abstract

We study heat kernel estimates for symmetric pure jump processes on general metric measure spaces. Building on recent progress in the local setting due to S.~Eriksson-Bique, we develop a non-local version of the Whitney blending technique and use it to relate stable-like heat kernel estimates to capacity upper bounds. Under two-sided stable-like bounds on the jump kernel, we show that a capacity upper bound across annuli implies a cutoff Sobolev inequality, and we obtain a characterization of stable-like heat kernel estimates in terms of these conditions. As a consequence, we give an affirmative answer to a conjecture of A. Grigor'yan, E. Hu, and J. Hu.