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arXiv · 1104.5265

The Point in Weak Semiprojectivity and AANR Compacta

Terry A. Loring
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Abstract

We initiate the study of pointed approximative absolute neighborhood retracts. Our motivation is to generate examples of C*-algebras that behave in unexpected ways with respect to weak semiprojectivity. We consider both weak semiprojectivity (WSP) and weak semiprojectivity with respect to the class of unital C*-algebras (WSP1). For a non-unital C*-algebra, these are different properties. One example shows a C*-algebra can fail to be WSP while its unitization is WSP. Another example shows WSP1 is not closed under direct sums.

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Terry A. Loring. 2011-04-27. The Point in Weak Semiprojectivity and AANR Compacta. https://arxiv.org/abs/1104.5265

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