Preprint:
AN ASYMPTOTIC THEORY FOR RANDOMLY-FORCED DISCRETE NONLINEAR HEAT EQUATIONS

Mohammud Foondun and Davar Khoshnevisan

Abstract. We study discrete nonlinear parabolic stochastic heat equations of the form un+1(x) - un (x) = Lun + σ(un(x))ξn(x), for positive integers n and x in Zd, where the ξ's denote random forcing and L the generator of a random walk on Zd. Under mild conditions, we prove that the preceding stochastic PDE has a unique solution that grows at most exponentially in time. And that, under natural conditions, it is "weakly intermittent." Along the way, we establish a comparison principle as well as a finite-support property.

Keywords. Stochastic heat equation, intermittency.

AMS Classification (2000). Primary. 35R60, 37H10, 60H15; Secondary. 82B44.

Support. The research of DK was supported in part by a grant from the U.S. National Science Foundation.

Pre/E-Prints. This paper is available in

Mohammud Foondun
Department of Mathematics
University of Utah
155 S, 1400 E JWB 233
Salt Lake City, UT 84112-0090, U.S.A.
mohammud@math.utah.edu
Davar Khoshnevisan
Department of Mathematics
University of Utah
155 S, 1400 E JWB 233
Salt Lake City, UT 84112-0090, U.S.A.
davar@math.utah.edu

Last Update: November 5, 2008
© 2008 - Mohammud Foondun and Davar Khoshnevisan