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arXiv · 2205.00854

On the Caldararu and Willwacher conjectures

Alexey Kalugin
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Abstract

In the present paper, we study a relation between the cohomology of moduli stacks of smooth and proper curves $\mathcal M_{g,n}$ and the cohomology of ribbon graph complexes. The main results of this work are proofs of T. Willwacher's conjecture and A. C$\check{\mathrm a}$ld$\check{\mathrm a}$raru's conjecture about the cohomology of the Bridgeland differential. We also discuss the relation to string topology and the Chan-Galatius-Payne theorem about the weight zero part of the compactly supported cohomology of $\mathcal M_{g,n}.$

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Alexey Kalugin. 2022-05-02. On the Caldararu and Willwacher conjectures. https://arxiv.org/abs/2205.00854

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