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arXiv · 2006.11960

Galkin's lower bound conjecture holds for the Grassmannian

La'Tier Evans·Lisa Schneider·Ryan M. Shifler·Laura Short·Stephanie Warman
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Abstract

Let Gr$(k,n)$ be the Grassmannian. The quantum multiplication by the first Chern class $c_1({\rm Gr}(k,n))$ induces an endomorphism $\hat c_1$ of the finite-dimensional vector space $\mathrm{QH}^*({\rm Gr}(k,n))_{|q=1}$ specialized at $q=1$. Our main result is a case that a conjecture by Galkin holds. It states that the largest real eigenvalue of $\hat{c}_1$ is greater than or equal to $\dim {\rm Gr}(k,n)$+1 with equality if and only if Gr$(k,n)=\mathbb{P}^{n-1}$.

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La'Tier Evans, Lisa Schneider, Ryan M. Shifler, Laura Short, Stephanie Warman. 2020-06-22. Galkin's lower bound conjecture holds for the Grassmannian. https://arxiv.org/abs/2006.11960

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