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arXiv 0710.0337math-phhep-thmath.COmath.MP
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曲面图与弦论的配分函数

Graphs on Surfaces and the Partition Function of String Theory

J. Manuel Garcia-Islas

摘要:

曲面上的图是图论中纯数学的一个活跃课题。它也被应用于物理学,并涉及离散和连续数学。本文给出了图论与离散弦论数学物理之间关系的形式化数学描述。在本说明中,我们提出的问题的组合世界的真正重要的图论。论文的数学细节如下:有一个玻色弦论的配分函数的组合描述。在这种组合描述中,弦世界单被认为是单纯的,它被认为是一个组合图。也可以说,我们在闭曲面中有图的嵌入。从这个过程中产生的离散配分函数给出了封闭曲面三角剖分的总和。这被称为真空配分函数。配分函数的精确计算依赖于包括计算图的所有非同构三角剖分和所有生成树的组合计算。精确计算的配分函数原来是非常复杂的,但我们显示的情况下,任何封闭的定向表面的精确表达式计算。我们提出了一个明确的计算的领域和它是如何做的环面,并为不可定向的情况下的射影平面。

英文摘要:

Graphs on surfaces is an active topic of pure mathematics belonging to graph theory. It has also been applied to physics and relates discrete and continuous mathematics. In this paper we present a formal mathematical description of the relation between graph theory and the mathematical physics of discrete string theory. In this description we present problems of the combinatorial world of real importance for graph theorists. The mathematical details of the paper are as follows: There is a combinatorial description of the partition function of bosonic string theory. In this combinatorial description the string world sheet is thought as simplicial and it is considered as a combinatorial graph. It can also be said that we have embeddings of graphs in closed surfaces. The discrete partition function which results from this procedure gives a sum over triangulations of closed surfaces. This is known as the vacuum partition function. The precise calculation of the partition function depends on combinatorial calculations involving counting all non-isomorphic triangulations and all spanning trees of a graph. The exact computation of the partition function turns out to be very complicated, however we show the exact expressions for its computation for the case of any closed orientable surface. We present a clear computation for the sphere and the way it is done for the torus, and for the non-orientable case of the projective plane.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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