RT Journal Article T1 Nonlocal heat equations: Regularizing effect, decay estimates and Nash inequalities A1 Brandle Cerqueira, Cristina A1 Pablo Martínez, Arturo de AB We study the short and large time behaviour of solutions of nonlocal heat equations of the form ∂tu+Lu=0. Here L is an integral operator given by a symmetric nonnegative kernel of Lévy type, that includes bounded and unbounded transition probability densities. We characterize when a regularizing effect occurs for small times and obtain Lq-Lp decay estimates, 1≤q