Title of article :
Browder–Weyl theorems, tensor products and multiplications
Author/Authors :
Duggal، نويسنده , , B.P.، نويسنده ,
Issue Information :
دوهفته نامه با شماره پیاپی سال 2009
Abstract :
A Banach space operator T ∈ B ( X ) satisfies Browderʹs theorem if the complement of the Weyl spectrum σ w ( T ) of T in σ ( T ) equals the set of Riesz points of T; T is polaroid if the isolated points of σ ( T ) are poles (no restriction on rank) of the resolvent of T. Let Φ ( T ) denote the set of Fredholm points of T. Browderʹs theorem transfers from A , B ∈ B ( X ) to S = L A R B (resp., S = A ⊗ B ) if and only if A and B ∗ (resp., A and B) have SVEP at points μ ∈ Φ ( A ) and ν ∈ Φ ( B ) for which λ = μ ν ∉ σ w ( S ) . If A and B are finitely polaroid, then the polaroid property transfers from A ∈ B ( X ) and B ∈ B ( Y ) to L A R B ; again, restricting ourselves to the completion of X ⊗ Y in the projective topology, if A and B are finitely polaroid, then the polaroid property transfers from A ∈ B ( X ) and B ∈ B ( Y ) to A ⊗ B .
Keywords :
Hereditarily normaloid operators , Banach space , Browderיs theorem , Weylיs theorem , Single-valued extension property , Polaroid operator
Journal title :
Journal of Mathematical Analysis and Applications
Journal title :
Journal of Mathematical Analysis and Applications