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A presentation for the Chow ring of \bar{M}_{0,2}(P^1,2)

Jonathan A. Cox
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Abstract

We give a presentation for the Chow ring of the moduli space of degree two stable maps from two-pointed rational curves to P^1. Also, integrals of of all degree four monomials in the hyperplane pullbacks and boundary divisors of this ring are computed using equivariant intersection theory. Finally, the presentation is used to give a new computation of the (previously known) values of the genus zero, degree two, two-pointed gravitational correlators of P^1. This article is a sequel to math.AG/0501322, although the only information truly needed from that article is the Poincare polynomial of the moduli space under consideration.

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Jonathan A. Cox. 2005-05-10. A presentation for the Chow ring of \bar{M}_{0,2}(P^1,2). https://arxiv.org/abs/math/0504575

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