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arXiv · 1205.0420

On the operad structure of admissible G-covers

Dan Petersen
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Abstract

We describe the modular operad structure on the moduli spaces of pointed stable curves equipped with an admissible $G$-cover. To do this we are forced to introduce the notion of an operad colored not by a set but by the objects of a category. This construction interpolates in a sense between `framed' and `colored' versions of operads; we hope that it will be of independent interest. An algebra over this operad is the same thing as a $G$-equivariant CohFT, as defined by Jarvis, Kaufmann and Kimura. We prove that the (orbifold) Gromov--Witten invariants of global quotients $[X/G]$ give examples of $G$-CohFTs.

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Dan Petersen. 2012-05-02. On the operad structure of admissible G-covers. https://doi.org/10.2140/ant.2013.7.1953

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