ScalingStacks

0PDS

Remark 8.2.19. Consider ZZ the singular curve quotient of oriented 𝐑{\mathbf{R}} by the identification of two points. Take MM to be the single exceptional point of ZZ. The construction above applied to 𝒮M∙​(Z){\mathcal{S}}_{M}^{\bullet}(Z) gives a category where going twice around the circle, avoiding the loop, is non-zero (cf picture below), while it is not represented by a smooth path in ZξZ_{\xi}. Theorem 8.2.18 does not hold because MM is too small.

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Original mathematics by the credited authors. Source collection and HTML conversion remain in progress.

Andrew Manion, Raphael Rouquier

Original source: arXiv:2009.09627v2