A bounded linear operation
T : X → Y between Banach spaces is said to be weakly compact if it takes bounded
sequences onto sequences which have a weakly convergent subsequence. Let W[X,Y ]
denote the weakly compact operators from X to Y , B[X,Y ], the bounded operators
and K[X,Y ], the compact operators. Now W[X,Y ] forms a closed subalgebra of
B[X,Y ] and for X = Y , W[X,X] is a closed (in the uniform topology) two-sided
ideal of B[X,X]. The purpose of this note is to construct a faithful representation of
the Generalized Calkin Algebra B[X,X]∕K[X,X], which parallels a similar
representation of B[X,X]∕K[X,X] in Buoni, Harte and Wickstead, “ Upper and
lower Fredholm spectra”.
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