78 citations · 300 across the 55 of their papers we have counts for
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Uniqueness of unconditional bases in c_0-products
Peter G. Casazza, Nigel J. Kalton
We give counterexamples to a conjecture of Bourgain, Casazza, Lindenstrauss and Tzafriri that if X has a unique unconditional basis (up to permutation) then so does c_0(X). In part…
Frames of translates
Peter G. Casazza, Ole Christensen, Nigel J. Kalton
We give necessary and sufficient conditions for a subfamily of regularly spaced translates of a function to form a frame (resp. a Riesz basis) for its span. One consequence is that…
Some Applications of Operator-Valued Herglotz Functions
Fritz Gesztesy, Nigel J. Kalton, Konstantin A. Makarov +1
We consider operator-valued Herglotz functions and their applications to self-adjoint perturbations of self-adjoint operators and self-adjoint extensions of densely defined closed…