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Irreducible Components of Exotic Springer fibres II: The Exotic Robinson-Schensted Algorithm

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 نشر من قبل Neil Saunders
 تاريخ النشر 2017
  مجال البحث
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Katos exotic nilpotent cone was introduced as a substitute for the ordinary nilpotent cone of type C with cleaner properties. The geometric Robinson-Schensted correspondence is obtained by parametrizing the irreducible components of the Steinberg variety (the conormal variety for the action of a semisimple group on two copies of its flag variety); in type A the bijection coincides with the classical Robinson-Schensted algorithm for the symmetric group. Here we give a combinatorial description of the bijection obtained by using the exotic nilpotent cone instead of ordinary type C nilpotent cone in the geometric Robinson-Schensted correspondence; we refer this as the exotic Robinson-Schensted bijection. This is interesting from a combinatorial perspective, and not a naive extension of the type A Robinson-Schensted bijection.



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