Search results for "rational cohomology"

showing 4 items of 4 documents

A combinatorial algorithm related to the geometry of the moduli space of pointed curves

2002

As pointed out in Arbarello and Cornalba ( J. Alg. Geom. 5 (1996), 705–749), a theorem due to Di Francesco, Itzykson, and Zuber (see Di Francesco, Itzykson, and Zuber, Commun. Math. Phys. 151 (1993), 193–219) should yield new relations among cohomology classes of the moduli space of pointed curves. The coefficients appearing in these new relations can be determined by the algorithm we introduce in this paper.

Settore MAT/02 - AlgebraSettore MAT/03 - Geometriarational cohomology class moduli spaces of pointed curvesSchur Q-polynomials; projective representations; moduli space of curves
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Generalized Hodge classes on the moduli space of curves

2003

On the moduli space of curves we consider the cohomology classes which can be viewed as a generalization of the Hodge classes λi defined by Mumford in [6]. Following the methods used in this paper, we prove that these classes belong to the tautological ring of the moduli space.

Settore MAT/03 - Geometriarational cohomology classes hodge classes
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Combinatorics of Mumford-Morita-Miller classes in low genus

2003

Here we use elementary combinatorial arguments to give explicit formulae and relations for some cohomology classes of moduli spaces of stable curves of low genus.

rational cohomology classes moduli spaces of rational curvesSettore MAT/03 - Geometria
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Calculating cohomology groups of $overline M_0,n(mathbb P^r,d)$

2003

Here we investigate the rational cohomology of the moduli space ℳ̄0,n (ℙr,d) of degree d stable maps from n-pointed rational curves to ℙr. We obtain partial results for small values of d with an inductive method inspired by a paper of Enrico Arbarello and Maurizio Cornalba.

rational cohomology moduli space of stable mapsSettore MAT/03 - Geometria
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