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arXiv · 1706.07079

Cohomology of the flag variety under PBW degenerations

Martina Lanini·Elisabetta Strickland
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Abstract

PBW degenerations are a particularly nice family of flat degenerations of type A flag varieties. We show that the cohomology of any PBW degeneration of the flag variety surjects onto the cohomology of the original flag variety, and that this holds in an equivariant setting too. We also prove that the same is true in the symplectic setting when considering Feigin's linear degeneration of the symplectic flag variety.

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BibTeXRIS

Martina Lanini, Elisabetta Strickland. 2017-06-21. Cohomology of the flag variety under PBW degenerations. https://arxiv.org/abs/1706.07079

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