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Title: Rank-finiteness for modular categories
We prove a rank-finiteness conjecture for modular categories: up to equivalence, there are only finitely many modular categories of any fixed rank. Our technical advance is a generalization of the Cauchy theorem in group theory to the context of spherical fusion categories. For a modular category C \mathcal {C} with N = ord ( T ) N= \textrm {ord}(T) , the order of the modular T T -matrix, the Cauchy theorem says that the set of primes dividing the global quantum dimension D 2 D^2 in the Dedekind domain Z [ e 2 Ο€ i N ] \mathbb {Z}[e^{\frac {2\pi i}{N}}] is identical to that of N N .  more » « less
Award ID(s):
1108725
PAR ID:
10301204
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Journal of the American Mathematical Society
Volume:
29
Issue:
3
ISSN:
0894-0347
Page Range / eLocation ID:
857 to 881
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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