In this paper, we show that for a semi-shift the analytic spec-tral subspace coincides with the algebraic spectral subspace. Using this result, we have the following result. Let T be a decomposable operator on a Banach space X and let S be a semi-shif...
In this paper, we show that for a semi-shift the analytic spec-tral subspace coincides with the algebraic spectral subspace. Using this result, we have the following result. Let T be a decomposable operator on a Banach space X and let S be a semi-shift on a Banach space Y. Then every linear operator µ : X ! Y with Sµ = µT is necessarily continuous.