ArticleOriginal scientific text
Title
Analyticity of transition semigroups and closability of bilinear forms in Hilbert spaces
Authors 1
Affiliations
- Dipartimento di Matematica, Politecnico di Milano, Piazza Leonardo da Vinci, 32 20133 Milano, Italy
Abstract
We consider a semigroup acting on real-valued functions defined in a Hilbert space H, arising as a transition semigroup of a given stochastic process in H. We find sufficient conditions for analyticity of the semigroup in the space, where μ is a gaussian measure in H, intrinsically related to the process. We show that the infinitesimal generator of the semigroup is associated with a bilinear closed coercive form in . A closability criterion for such forms is presented. Examples are also given.
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