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arXiv · 1905.05630

The Hadamard product in a crossed product C*-algebra

Erik Christensen
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Abstract

We show that for a C*-algebra A and a discrete group G with an action of G on A, the reduced crossed product C*-algebra possesses a natural generalization of the convolution product, which we suggest should be named the Hadamard product. We show that this product has a natural Stinespring representation and we lift some known results on block Schur products to this setting, but we also show that the block Schur product is a special case of the Hadamard product in a crossed product algebra.

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Erik Christensen. 2019-05-14. The Hadamard product in a crossed product C*-algebra. https://arxiv.org/abs/1905.05630

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