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arXiv · 0912.2126

Non-canonical isomorphisms

Stephen Lack
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Abstract

We give two examples of categorical axioms asserting that a canonically defined natural transformation is invertible where the invertibility of any natural transformation implies that the canonical one is invertible. The first example is distributive categories, the second (semi-)additive ones. We show that each follows from a general result about monoidal functors.

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Stephen Lack. 2009-12-10. Non-canonical isomorphisms. https://doi.org/10.1016/j.jpaa.2011.07.012

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