The Chen–Ruan Cohomology of Weighted Projective Spaces

Jiang, Yunfeng

Canadian journal of mathematics, Tome 59 (2007) no. 5, pp. 981-1007

Résumé

In this paper we study the Chen–Ruan cohomology ring of weighted projective spaces. Given a weighted projective space ${{\mathbf{P}}^{n}}_{{{q}_{0}},\ldots ,{{q}_{n}}}$ , we determine all of its twisted sectors and the corresponding degree shifting numbers. The main result of this paper is that the obstruction bundle over any 3-multisector is a direct sum of line bundles which we use to compute the orbifold cup product. Finally we compute the Chen–Ruan cohomology ring of weighted projective space $\mathbf{P}_{1,\,2,\,2,\,3,3,\,{{3}^{\centerdot }}}^{5}$ .

Détail

DOI : 10.4153/CJM-2007-042-6

Mots-clés : 14N35, 53D45, Chen–Ruan cohomology, twisted sectors, toric varieties, weighted projective space, localization

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