标题： 弦理论方法研究广义二维杨-米尔斯理论 显示英文标题

标题： The String Theory Approach to Generalized 2D Yang-Mills Theory

摘要： 我们计算了定义在任意黎曼曲面上的 $SU(N)$ （和 $U(N)$）广义 $YM_2$ 理论的配分函数。以不可约表示求和表达的结果推广了普通YM_2理论的Rusakov公式。公式的图展开使我们能够推导出该模型类似于Gross-Taylor的弦描述。二维弦映射的求和被证明可以重现规范场理论的结果。带有高于一度分支点的映射以及“微观表面”在求和中起重要作用。我们讨论了背后的弦理论。 显示英文摘要

摘要： We calculate the partition function of the $SU(N)$ ( and $U(N)$) generalized $YM_2$ theory defined on an arbitrary Riemann surface. The result which is expressed as a sum over irreducible representations generalizes the Rusakov formula for ordinary YM_2 theory. A diagrammatic expansion of the formula enables us to derive a Gross-Taylor like stringy description of the model. A sum of 2D string maps is shown to reproduce the gauge theory results. Maps with branch points of degree higher than one, as well as ``microscopic surfaces'' play an important role in the sum. We discuss the underlying string theory.