D-branes in a topologically nontrivial B-field
D-branes in a topologically nontrivial B-field
复制标题
拓扑非平凡 B 场中的 D 膜
DOI：
10.4310/atmp.2000.v4.n1.a3
复制
发表时间：
1999
影响因子：
1.5
通讯作者：
A. Kapustin
中科院分区：
文献类型：
--
作者：
A. Kapustin
我们研究了在B场存在的情况下，以几个重合D-膜为结尾的开弦的全局世界面异常。我们表明，取消异常是可能的T 'Hooft磁通量的D-膜和B-场的拓扑类之间的相关性。我们的结果的一个应用是正确理解生活在D膜上的规范场的几何性质：它不是向量丛上的连接，而是某个非交换代数上的模上的连接。我们的论证适用于一般的闭弦背景。我们还解释了为什么在一个曲率为纯挠率的拓扑非平凡B-场的存在下，D-膜代表扭曲K-理论中的类，如E.维滕。
We study global worldsheet anomalies for open strings ending on several coincident D-branes in the presence of a B-field. We show that cancellation of anomalies is made possible by a correlation between the t'Hooft magnetic flux on the D-branes and the topological class of the B-field. One application of our results is a proper understanding of the geometric nature of the gauge field living on D-branes: rather than being a connection on a vector bundle, it is a connection on a module over a certain noncommutative algebra. Our argument works for a general closed string background. We also explain why in the presence of a topologically nontrivial B-field whose curvature is pure torsion D-branes represent classes in a twisted K-theory, as conjectured by E. Witten.