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Title: Fukaya categories of surfaces, spherical objects and mapping class groups
Abstract We prove that every spherical object in the derived Fukaya category of a closed surface of genus at least $$2$$ whose Chern character represents a nonzero Hochschild homology class is quasi-isomorphic to a simple closed curve equipped with a rank $$1$$ local system. (The homological hypothesis is necessary.) This largely answers a question of Haiden, Katzarkov and Kontsevich. It follows that there is a natural surjection from the autoequivalence group of the Fukaya category to the mapping class group. The proofs appeal to and illustrate numerous recent developments: quiver algebra models for wrapped categories, sheafifying the Fukaya category, equivariant Floer theory for finite and continuous group actions and homological mirror symmetry. An application to high-dimensional symplectic mapping class groups is included.  more » « less
Award ID(s):
1937869
PAR ID:
10249295
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Forum of Mathematics, Sigma
Volume:
9
ISSN:
2050-5094
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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