Aspects of the evolution dynamics of GR in the chiral formalism

手性形式主义中 GR 演化动力学的各个方面

• 批准号: 2601065
• 金额: --
• 依托单位: University of Nottingham
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2021
• 资助国家: 英国
• 起止时间: 2021 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2601065
• 关键词: Aspects; evolution; dynamics; GR; chiral

The aim of this project is to put to use the recently developed chiral formalism for perturbative calculations in 4D GR. In this formalism, there are two propagating fields, which are a tetrad field with its 16 components, and a chiral gauge field, which after gauge-fixing also has 16 components. This formalism is the gravity analog of the chiral formalism for Yang-Mills known by the name of Chalmers-Siegal action. In both formalism the action is polynomial, and so there is only a finite number of vertices - just cubic in YM, cubic and quartic in GR. The other distinguishing feather of this formalism is that the auxiliary fields do not propagate, i.e. from the 3 possible propagators connecting the two fields of the theory one vanishes exactly. This significantly simplifies Feynman diagram calculations. Some aspects of the chiral formalism for both YM and GR are described in reference. The aim of this project is to put this chiral GR perturbation theory to use, and compute some scattering amplitudes of interest. The project will start with warm up calculations of the 4-point graviton tree-level scattering (using the spinor helicity formalism). A more challenging computation is that of loop amplitudes, in particular those relevant in the non-relativistic limit that is needed for analysing the effective 2-body problem in GR (that is used for producing the gravitational wave-forms from BH mergers). THe project will aim to use the computationally powerful chiral perturbative formalism for gravity to simplify the calculations needed for producing the gravitational wave-forms.

这个项目的目的是把使用最近开发的手征形式主义的微扰计算在4D GR。在这种形式主义，有两个传播场，这是一个四分之一场与它的16个组件，和手征规范场，后规范固定也有16个组件。这种形式主义是杨-米尔斯的手征形式主义的重力模拟，称为Chalmers-Siegal作用。在这两种形式主义中，作用量都是多项式的，因此只有有限个顶点--YM中只有立方，GR中只有立方和四次。这种形式主义的另一个特点是辅助场不传播，即从连接理论的两个场的3个可能的传播子中，一个完全消失。这大大简化了费曼图的计算。参考文献中描述了YM和GR的手性形式主义的一些方面。本项目的目的是将手征GR微扰理论应用到实际中，并计算一些感兴趣的散射振幅。该项目将从四点引力子树级散射的热身计算开始（使用旋量螺旋度形式）。一个更具挑战性的计算是环振幅，特别是那些相关的非相对论性的限制，需要分析的有效2体问题在GR（用于产生的引力波的形式从BH合并）。该项目的目标是使用计算功能强大的手征微扰引力形式主义，以简化产生引力波所需的计算。