A basic identity for Kolmogorov operators in the space of continuous functions related to RDEs with multiplicative noise
arXiv:1212.5376
Abstract
We consider the Kolmogorov operator associated with a reaction-diffusion equation having polynomially growing reaction coefficient and perturbed by a noise of multiplicative type, in the Banach space of continuous functions. By analyzing the smoothing properties of the associated transition semigroup, we prove a modification of the classical identité du carré di champs that applies to the present non-Hilbertian setting. As an application of this identity, we construct the Sobolev space , where is an invariant measure for the system, and we prove the validity of the Poincaré inequality and of the spectral gap.
Key words: Stochastic reaction-diffusion equations, Kolmogorov operators, Poincaré inequality, spectral gap, Sobolev spaces in infinite dimensional spaces