arXiv math/04082652004-08math.SGmath.DG

A deRham model for Chen-Ruan cohomology ring of abelian orbifolds

Bohui Chen, Shengda Hu

备注：: 14 pages, corrected typos, added more references and shifted to presentation using groupoid
发表信息：: Math. Ann. 2006 (336) 1, 51-71

英文摘要：

We present a deRham model for Chen-Ruan cohomology ring of abelian orbifolds. We introduce the notion of \emph{twist factors} so that formally the stringy cohomology ring can be defined without going through pseudo-holomorphic orbifold curves. Thus our model can be viewed as the classical description of Chen-Ruan cohomology for abelian orbifolds. The model simplifies computation of Chen-Ruan cohomology ring. Using our model, we give a version of wall crossing formula.

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