arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1609.00732hep-thgr-qchep-ph
收藏

二维CFT的四维散射振幅和渐近对称性

4D Scattering Amplitudes and Asymptotic Symmetries from 2D CFT

Clifford Cheung, Anton de la Fuente, Raman Sundrum

摘要:

本文用天球上二维连续傅里叶变换的语言重新表述了四维平坦空间规范理论和引力的散射振幅。由此产生的CFT结构表现出一个OPE构造的4D共线奇点,以及无限维Kac-Moody和维拉索罗代数编码的4D平坦空间的渐近对称性。我们得到这些结果重铸4D动力学方面的一个方便的叶理平坦的空间到3D欧几里德AdS和洛伦兹dS几何。树级散射振幅采用连续(A)dS模式的Witten图的形式,其又通过(A)dS/CFT字典等效于CFT散射器。二维守恒流的沃德恒等式是四维软定理的对偶,而无质量(A)dS模的体边界传播子是规范理论和引力的主导和次主导Weinberg软因子的叠加.一般来说,无质量(A)dS模是3D陈-西蒙斯规范场,描述了4D规范理论和引力的软单螺旋度扇区。与Chern-Simons理论的拓扑性质一致,Aharonov-Bohm效应记录了软辐射中硬粒子的“轨迹”,从而导致了规范和引力记忆的简单表征。硬过程之间的软粒子交换定义了卡茨-穆迪能级和Virasoro中心荷,从而与4D规范耦合和引力强度(以红外截止为单位)相关。最后,我们讨论了一个玩具模型的黑洞视界通过限制的Rindler区域。

英文摘要:

We reformulate the scattering amplitudes of 4D flat space gauge theory and gravity in the language of a 2D CFT on the celestial sphere. The resulting CFT structure exhibits an OPE constructed from 4D collinear singularities, as well as infinite-dimensional Kac-Moody and Virasoro algebras encoding the asymptotic symmetries of 4D flat space. We derive these results by recasting 4D dynamics in terms of a convenient foliation of flat space into 3D Euclidean AdS and Lorentzian dS geometries. Tree-level scattering amplitudes take the form of Witten diagrams for a continuum of (A)dS modes, which are in turn equivalent to CFT correlators via the (A)dS/CFT dictionary. The Ward identities for the 2D conserved currents are dual to 4D soft theorems, while the bulk-boundary propagators of massless (A)dS modes are superpositions of the leading and subleading Weinberg soft factors of gauge theory and gravity. In general, the massless (A)dS modes are 3D Chern-Simons gauge fields describing the soft, single helicity sectors of 4D gauge theory and gravity. Consistent with the topological nature of Chern-Simons theory, Aharonov-Bohm effects record the "tracks" of hard particles in the soft radiation, leading to a simple characterization of gauge and gravitational memories. Soft particle exchanges between hard processes define the Kac-Moody level and Virasoro central charge, which are thereby related to the 4D gauge coupling and gravitational strength in units of an infrared cutoff. Finally, we discuss a toy model for black hole horizons via a restriction to the Rindler region.

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。

↑