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The genus zero Gromov-Witten invariants of [Sym^2 P^2]

Jonathan Wise
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Abstract

We study the Abramovich--Vistoli moduli space of genus zero orbifold stable maps to [Sym^2 P^2], the stack symmetric square of P^2. This compactifies the moduli space of stable maps from hyperelliptic curves to P^2, and we show that all genus zero Gromov--Witten invariants are determined from trivial enumerative geometry of hyperelliptic curves. We also show how the genus zero Gromov--Witten invariants can be used to determine the number of hyperelliptic curves of degree d and genus g interpolating 3d + 1 generic points in P^2. Comparing our method to that of Graber for calculating the same numbers, we verify an example of the crepant resolution conjecture.

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Jonathan Wise. 2008-07-25. The genus zero Gromov-Witten invariants of [Sym^2 P^2]. https://arxiv.org/abs/math/0702219

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