A Partial Horn Recursion in the Cohomology of Flag Varieties
نویسنده
چکیده
Horn recursion is a term used to describe when non-vanishing products of Schubert classes in the cohomology of complex flag varieties are characterized by inequalities parameterized by similar non-vanishing products in the cohomology of “smaller” flag varieties. We consider the type A partial flag variety and find that its cohomology exhibits a Horn recursion on a certain deformation of the cup product defined by Belkale and Kumar in [2]. We also show that if a product of Schubert classes is non-vanishing on this deformation, then the associated structure constant can be written in terms of structure constants coming from induced Grassmannians.
منابع مشابه
HORN RECURSION FOR A NEW PRODUCT IN THE COHOMOLOGY OF PARTIAL FLAG VARIETIES SLn/P
Horn recursion is a term used to describe when non-vanishing products of Schubert classes in the cohomology of flag varieties G/P are characterized by inequalities parameterized by similar non-vanishing products in the cohomology of “smaller” flag varieties. We consider the partial flag variety SLn/P and find that H ∗(SLn/P ) exhibits Horn recursion on a certain deformation of the cup product. ...
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Horn recursion is a term used to describe when non-vanishing products of Schubert classes in the cohomology of flag varieties G/P are characterized by inequalities parameterized by similar non-vanishing products in the cohomology of ”smaller” flag varieties. We consider the partial flag variety SLn/P and find that H (SLn/P ) exhibits Horn recursion on a certain deformation of the cup product. W...
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