8 papers
Gerbes and twisted orbifold quantum cohomology
Jianzhong Pan, Yongbin Ruan, Xiaoqin Yin
In this article, we construct an orbifold quantum cohomology twisted by a flat gerbe. Then we compute these invariants in the case of a smooth manifold and a discrete torsion on a…
Stringy orbifolds
Yongbin Ruan
Recently, there is an explosive growth of activities to understand stringy properties of orbifolds. In this article, we survey some of recent developments.
Cohomology ring of crepant resolutions of orbifolds
Yongbin Ruan
Motivated by physics, we propose two conjectures regarding the cohomology ring of the crepant resolutions of orbifolds and cohomological invariants of K-equivalent manifolds.
Orbifold Gromov-Witten Theory
Weimin Chen, Yongbin Ruan
In this article, we introduce the notion of good map and use it to establish Gromov-Witten theory for orbifolds.
Orbifold Quantum Cohomology
Weimin Chen, Yongbin Ruan
This is a research announcement of the theory of orbifold quantum cohomology.
Discrete torsion and twisted orbifold cohomology
Yongbin Ruan
In this article, we study the twisting procedure of orbifold cohomology. We introduce local system and construct twisted orbifold cohomology. Then, we generalize Vafa-Witten's noti…