The system will be going down for regular maintenance. Please save your work and logout.
Exact observability, square functions and spectral theory
Language
en
Article de revue
This item was published in
Journal of Functional Analysis. 2012-03-15, vol. 262, n° 6, p. 2903-2927
Elsevier
English Abstract
In the first part of this article we introduce the notion of a backward-forward conditioning (BFC) system that generalises the notion of zero-class admissibiliy introduced in [Xu,Liu,Yung]. We can show that unless the ...Read more >
In the first part of this article we introduce the notion of a backward-forward conditioning (BFC) system that generalises the notion of zero-class admissibiliy introduced in [Xu,Liu,Yung]. We can show that unless the spectum contains a halfplane, the BFC property occurs only in siutations where the underlying semigroup extends to a group. In a second part we present a sufficient condition for exact observability in Banach spaces that is designed for infinite-dimensional output spaces and general strongly continuous semigroups. To obtain this we make use of certain weighted square function estimates. Specialising to the Hilbert space situation we obtain a result for contraction semigroups without an analyticity condition on the semigroup.Read less <
English Keywords
spectral theory of semigroups and groups
square function estimates
$H^\infty$ functional calculus
Exact observability
admissibility
Origin
Hal imported