We consider the limiting behavior of discriminants, by which we mean informally the locus in
some parameter space of some type of object where the objects have certain singularities …

arXiv:math/0011149v2 [math.AG] 11 Mar 2001 Page 1 arXiv:math/0011149v2 [math.AG] 11
Mar 2001 Stringy geometry and topology of orbifolds1 Yongbin Ruan Department of …

We survey the push-forward formula for elliptic class and various applications obtained in
the papers by L. Borisov and the author. We then discuss the ring of quasi-Jacobi forms …

We establish a correspondence between orbifold and singular elliptic genera of a global
quotient. While the former is defined in terms of the fixed point set of the action, the latter is …

In this paper, we study the perturbative aspects of a twisted version of the two-dimensional
(0, 2) heterotic sigma model on a holomorphic gauge bundle E over a complex, hermitian …

We show that the chiral algebras of N=(0, 2) sigma models with no left-moving fermions are
totally trivialized by worldsheet instantons for flag manifold target spaces. Consequently …

We compare the moonshine observation of Eguchi, Ooguri and Tachikawa relating the
Mathieu group M_24 and the complex elliptic genus of a K3 surface with the symmetries of …

We prove generating series formulae for suitable twisted characteristic classes of symmetric
products of a singular complex quasi-projective variety. More concretely, we study homology …

We give a new proof of formulae for the generating series of (Hodge) genera of symmetric
products X (n) with coefficients, which hold for complex quasi-projective varieties X with any …

arXiv:math/0109005v1 [math.DG] 1 Sep 2001 Page 1 arXiv:math/0109005v1 [math.DG] 1 Sep
2001 On orbifold elliptic genus Chongying DONG1, Kefeng LIU2, Xiaonan MA3 0 Introduction …