Exponential stability of c0-semigroup via Lyapunov inequality in Banach space

Abstract

We give a relation between the exponential stability of $ C_{0}- $semigroup $ \textbf{T}=\left\lbrace T(t) \right\rbrace_{t\geq 0} $ and the solutions of Lyapunov inequality \( \left\langle QAx,x\right\langle +\left\langle Qx,Ax\right\langle \leq -||x||^{2}, \) in $ B^{+}(X,X^{*}) $, with $ X $ is a Banach space. The solutions of this inequality characterizes, the boundedness of the resolvent $ R(\lambda,A) $ inside and outside of the left half-plane $ \Re\lambda\geq 0 $, and also the left invertibility of the $ C_{0}- $semigroup T.