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arXiv · 1108.3089

Counting curves of any genus on P^2_7

M. Shoval·E. Shustin
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Abstract

We compute Gromov-Witten invariants of any genus for del Pezzo surfaces of degree $\ge2$. The genus zero invariants have been computed a long ago, Gromov-Witten invariants of any genus for del Pezzo surfaces of degree $\ge3$ have been found by Vakil. We solve the problem in two steps: (1) we consider the plane blown up at 6 points on a conic and one more point outside this conic (weak Fano surface), and, using techniques of tropical geometry, obtain a Caporaso-Harris type formula counting curves of any divisor class and genus subject to arbitrary tangency conditions with respect to the blown up conic, (2) then we express the Gromov-Witten invariants of the plane blown up at 7 points via enumerative invariants of the weak Fano surface, using Vakil's version of Abramovich-Bertram formula.

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M. Shoval, E. Shustin. 2011-08-15. Counting curves of any genus on P^2_7. https://arxiv.org/abs/1108.3089

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