Multiplicity in root components via geometric Satake
نویسندگان
چکیده
In this note we explicitly construct top-dimensional components of certain cyclic convolution varieties. These correspond (via the geometric Satake equivalence) to irreducible summands V(λ+μ−Nβ)⊂V(λ)⊗V(μ) for SLn+1(C), where N≥1 and β is a positive root. Furthermore, deduce from these constructions nontrivial lower bound on multiplicity subrepresentations when not simple Finally, demonstrate that all such can be realized as closures orbits.
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ژورنال
عنوان ژورنال: Communications in Algebra
سال: 2021
ISSN: ['1532-4125', '0092-7872']
DOI: https://doi.org/10.1080/00927872.2021.2015361