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Title: On an Equivalence of Divisors on $\overline {\text {M}}_{0,n}$ from Gromov-Witten Theory and Conformal Blocks

We consider a conjecture that identifies two types of base point free divisors on$\overline {\text {M}}_{0,n}$M¯0,n. The first arises from Gromov-Witten theory of a Grassmannian. The second comes from first Chern classes of vector bundles associated with simple Lie algebras in type A. Here we reduce this conjecture on$\overline {\text {M}}_{0,n}$M¯0,nto the same statement forn= 4. A reinterpretation leads to a proof of the conjecture on$\overline {\text {M}}_{0,n}$M¯0,nfor a large class, and we give sufficient conditions for the non-vanishing of these divisors.

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Transformation Groups
Springer Science + Business Media
Sponsoring Org:
National Science Foundation
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