A note on the common spectral properties for bounded linear operators


Hassane Zguitti




Let X and Y be Banach spaces, A : X → Y and B, C : Y → X be bounded linear operators. We prove that if A(BA) 2 = ABACA = ACABA = (AC) 2 A, then σ * (AC) {0} = σ * (BA) {0} where σ * runs over a large of spectra originated by regularities,