Pointwise Green's function bounds for multidimensional scalar viscous shock fronts

We determine detailed pointwise bounds for the Green's function of the linearized operator about a multidimensional scalar viscous shock front. These extend the pointwise semigroup, methods introduced by Howard and Zumbrun in the one-dimensional case to multidimensions, sharpening L-P estimates obtained by Goodman and Miller using a weighted norm approach. Moreover, our results apply to shocks of arbitrary strength, as previous results did not. As described in a companion paper, the bounds we obtain are sufficient to give a straightforward treatment of the nonlinear L-P-asymptotic behavior of the front under small perturbation. The analysis of the multidimensional case involves several new features not found in the one-dimensional case, concerned with the geometry of propagating signals. (C) 2002 Elsevier Science (USA).