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Title: A rigid local system with monodromy group the big Conway group $2.\mathsf {Co}_1$ and two others with monodromy group the Suzuki group $6.{{Suz}}$
Award ID(s):
1840702
NSF-PAR ID:
10221118
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Transactions of the American Mathematical Society
Volume:
373
Issue:
3
ISSN:
0002-9947
Page Range / eLocation ID:
2007 to 2044
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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    We first develop some basic facts about hypergeometric sheaves on the multiplicative group [Formula: see text] in characteristic [Formula: see text]. Certain of their Kummer pullbacks extend to irreducible local systems on the affine line in characteristic [Formula: see text]. One of these, of rank [Formula: see text] in characteristic [Formula: see text], turns out to have the Conway group [Formula: see text], in its irreducible orthogonal representation of degree [Formula: see text], as its arithmetic and geometric monodromy groups. 
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