A non-spectral representation of shift semigroups.
If -A is the generator of an equibounded -semigroup and 0 < Re α < m (m integer), its fractional power can be described in terms of the semigroup, through a formula that is only valid if a certain function is nonzero. This paper is devoted to the study of the zeros of .
Convergence of semigroups which do not converge in the Trotter-Kato-Neveu sense is considered.
In stochastic partial differential equations it is important to have pathwise regularity properties of stochastic convolutions. In this note we present a new sufficient condition for the pathwise continuity of stochastic convolutions in Banach spaces.
Motivated by applications to transition semigroups, we introduce the notion of a norming dual pair and study a Pettis-type integral on such pairs. In particular, we establish a sufficient condition for integrability. We also introduce and study a class of semigroups on such dual pairs which are an abstract version of transition semigroups. Using our results, we give conditions ensuring that a semigroup consisting of kernel operators has a Laplace transform which also consists of kernel operators....
Let T be a semigroup of linear contractions on a Banach space X, and let . Then is the annihilator of the bounded trajectories of T*. If the unitary spectrum of T is countable, then is the annihilator of the unitary eigenvectors of T*, and for each x in X.