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arXiv · 2008.13765

An affine approach to Peterson comparison

Linda Chen·Elizabeth Milićević·Jennifer Morse
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Abstract

The Peterson comparison formula proved by Woodward relates the three-pointed Gromov-Witten invariants for the quantum cohomology of partial flag varieties to those for the complete flag. Another such comparison can be obtained by composing a combinatorial version of the Peterson isomorphism with a result of Lapointe and Morse relating quantum Littlewood-Richardson coefficients for the Grassmannian to k-Schur analogs in the homology of the affine Grassmannian obtained by adding rim hooks. We show that these comparisons on quantum cohomology are equivalent, up to Postnikov's strange duality isomorphism.

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Linda Chen, Elizabeth Milićević, Jennifer Morse. 2020-08-31. An affine approach to Peterson comparison. https://arxiv.org/abs/2008.13765

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