© 2000 by London Mathematical Society
© The London Mathematical Society
Off-Diagonal Bounds of Non-Gaussian Type for the Dirichlet Heat Kernel
Dipartimento di Matematica, Politecnico di Torino Corso Duca degli Abruzzi 24, 10129 Torino, Italy, grillo{at}calvino.polito.it
Received 10 May 1999.
The paper considers the heat kernel K
(t, x, y) of the operator
on a proper Euclidean domain
, with Dirichlet boundary conditions. A general pointwise lower bound for K
, which is valid for t larger than a suitable t0(x,y), is proved (the short-time behaviour being well understood). The resulting non-Gaussian bounds describe simultaneously both the case of bounded domains and the case, modelled on the half-space example, of domains which satisfy a twisted infinite internal cone condition. Bounds for the Green's function are given as well.