Combinatorics of minuscule representations (Cambridge Tracts in Mathematics 199) By R. M. Green
Combinatorics of minuscule representations (Cambridge Tracts in Mathematics 199) By R. M. Green
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微小表示的组合(剑桥数学丛书 199) 作者:R. M. Green
DOI:
10.1112/blms/bdu112
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发表时间:
2015
影响因子:
0.9
通讯作者:
V. Reiner
中科院分区:
文献类型:
--
作者:
V. Reiner
To be a minuscule representation of a complex simple Lie algebra|| is to be ‘as small as possible’: not only irreducible and finite-dimensional, but with all weights in the same orbit under the action of the Weyl group||. In particular, the highest weight|| has one-dimensional weight space, so all of its weight spaces are one-dimensional. It turns out to be fruitful to partially order the set of weights||, defining the weight poset in which|| when|| is a non-negative sum of positive roots. As explained in RM Green's book under review here, poset structures are the key to a minuscule representation's many special properties, making it simpler than a typical||-irreducible.Minuscule representations exist only in types||. In type|| they are the exterior powers|| of the natural representation|| for the Lie algebra|| of trace zero matrices in||. Here the Weyl group|| of type|| can be taken to be the symmetric group|| permuting the standard basis||. The monomial wedges|| give a basis of weight vectors for||, depicted here for||, ordered as in the weight poset: