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arXiv 2101.09205hep-thmath-phmath.MP
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QFT中的等变和超对称局部化

Equivariant and supersymmetric localization in QFT

Paolo Rossi

摘要:

等变局部化理论是一个强大的工具,在过去的三十年里,它被广泛地用于数学和物理中,以优雅地获得精确的积分公式。这些积分公式在等变上同调的数学形式中得到证明,等变上同调是标准上同调理论的一种变体,它包含了作用于手头空间的对称群的存在。这种形式的一个适当的无限维推广适用于某一类具有超对称性的量子场论。在这篇论文中,我们回顾了等变定域的形式及其在量子力学和QFT中的一些应用。我们从阿贝尔群作用情形下有限维积分的等变上同调和相关局部化定理的数学描述开始,然后讨论它们在QFT中无限维路径积分的形式应用.我们总结了文献中计算不同维数超对称算子的配分函数和期望值的一些例子。对于1维QFT,即QM,我们回顾了应用本地化原理推导的Atiyah-Singer指数定理适用于狄拉克算子的扭曲旋量丛。在3维和4维中,我们研究了超对称规范理论中某些威尔逊圈的期望值的计算及其与用“矩阵模型“描述的0维理论的关系。最后,我们回顾了应用于2维杨-米尔斯理论的非阿贝尔局部化的形式主义及其在标准“物理”理论和相关“上同调”公式之间的映射中的应用。

英文摘要:

Equivariant localization theory is a powerful tool that has been extensively used in the past thirty years to elegantly obtain exact integration formulas, in both mathematics and physics. These integration formulas are proved within the mathematical formalism of equivariant cohomology, a variant of standard cohomology theory that incorporates the presence of a symmetry group acting on the space at hand. A suitable infinite-dimensional generalization of this formalism is applicable to a certain class of Quantum Field Theories (QFT) endowed with supersymmetry. In this thesis we review the formalism of equivariant localization and some of its applications in Quantum Mechanics (QM) and QFT. We start from the mathematical description of equivariant cohomology and related localization theorems of finite-dimensional integrals in the case of an Abelian group action, and then we discuss their formal application to infinite-dimensional path integrals in QFT. We summarize some examples from the literature of computations of partition functions and expectation values of supersymmetric operators in various dimensions. For 1-dimensional QFT, that is QM, we review the application of the localization principle to the derivation of the Atiyah-Singer index theorem applied to the Dirac operator on a twisted spinor bundle. In 3 and 4 dimensions, we examine the computation of expectation values of certain Wilson loops in supersymmetric gauge theories and their relation to 0-dimensional theories described by "matrix models". Finally, we review the formalism of non-Abelian localization applied to 2-dimensional Yang-Mills theory and its application in the mapping between the standard "physical" theory and a related "cohomological" formulation.

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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