Bounding Ext for modules for algebraic groups, finite groups and quantum groups
نویسندگان
چکیده
منابع مشابه
Bounding Ext for Modules for Algebraic Groups, Finite Groups and Quantum Groups
Given a finite root system Φ, we show there is an integer c = c(Φ) such that dimExtG(L,L ) < c, for any reductive algebraic groupG with root system Φ and any irreducible rational G-modules L,L. We also prove that there is such a bound in the case of finite groups of Lie type, depending only on the root system and not on the underlying field. For quantum groups, we are able to obtain a similar r...
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ژورنال
عنوان ژورنال: Advances in Mathematics
سال: 2011
ISSN: 0001-8708
DOI: 10.1016/j.aim.2010.09.021