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On the number of subrepresentations of a general quiver representation

Harm Derksen·Aidan Schofield·Jerzy Weyman
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Abstract

It is well-known that the intersection multiplicities of Schubert classes in the Grassmanian are Littlewood-Richardson coefficients. We generalize this statement in the context of quiver representations. Here the intersection multiplicity of Schubert classes is replaced by the number of subrepresentations of a general quiver reprsentation, and the Littlewood-Richardson coefficients are replaced by the the dimension of a certain space of semiinvariants.

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Harm Derksen, Aidan Schofield, Jerzy Weyman. 2005-12-20. On the number of subrepresentations of a general quiver representation. https://arxiv.org/abs/math/0507393

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