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arXiv · 1409.0163

Relative (non-)formality of the little cubes operads and the algebraic Cerf Lemma

Victor Tourtchine·Thomas Willwacher
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Abstract

It is shown that the operad maps $E_n\to E_{n+k}$ are formal over the reals for $k\geq 2$ and non-formal for $k=1$. Furthermore we compute the cohomology of the deformation complex of the operad maps $E_{n}\to E_{n+1}$, proving an algebraic version of the Cerf Lemma.

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Victor Tourtchine, Thomas Willwacher. 2015-03-20. Relative (non-)formality of the little cubes operads and the algebraic Cerf Lemma. https://arxiv.org/abs/1409.0163

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