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arXiv 0910.2634gr-qc
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从时空观点看格林函数与辐射反应

Green Functions and Radiation Reaction From a Spacetime Perspective

Barry Wardell

摘要:

这项工作的基础是第一次充分应用泊松-怀斯曼-安德森方法的“匹配膨胀”计算的自我力作用在一个点粒子运动在弯曲的时空。该方法采用了两个扩展的格林函数分别是有效的“准本地”和“遥远的过去”制度,并在正常的邻域内匹配在一起。基于Avramidi的基本见解,我们提供了一个输运方程系统,用于确定关键的基本双张量,包括尾项V(x,x '),出现在格林函数的Hadamard形式中。这些双张量是从辐射反应和自作用力到弯曲时空中的量子场论和量子引力等一系列问题的核心。使用他们的输运方程,我们展示了如何准本地格林函数可以计算整个正常的邻居数值和作为一个协变泰勒级数展开。这些计算是对几个黑洞时空进行的。最后给出了匹配展开法的一个完整应用。计算是在球对称Nariai时空(dS_2 × S^2)的静态区域中进行的,在该区域中,用匹配展开方法计算作用在静态粒子上的标量自作用力。我们发现,匹配的扩展方法提供了洞察力的非局部性质的自作用力。史瓦西时空中的格林函数预计与纳里埃共享某些关键特征。这样,纳里埃时空就为深入了解黑洞时空中自作用力的非定域部分提供了一个肥沃的试验场。

英文摘要:

The basis of this work is the first full application of the Poisson-Wiseman-Anderson method of `matched expansions' to compute the self-force acting on a point particle moving in a curved spacetime. The method employs two expansions for the Green function which are respectively valid in the `quasilocal' and `distant past' regimes, and which are matched together within the normal neighborhood. Building on a fundamental insight due to Avramidi, we provide a system of transport equations for determining key fundamental bi-tensors, including the tail-term, V(x,x'), appearing in the Hadamard form of the Green function. These bitensors are central to a broad range of problems from radiation reaction and the self-force to quantum field theory in curved spacetime and quantum gravity. Using their transport equations, we show how the quasilocal Green function may be computed throughout the normal neighborhood both numerically and as a covariant Taylor series expansion. These calculations are carried out for several black hole spacetimes. Finally, we present a complete application of the method of matched expansions. The calculation is performed in a static region of the spherically symmetric Nariai spacetime (dS_2 X S^2), where the matched expansion method is applied to compute the scalar self-force acting on a static particle. We find that the matched expansion method provides insight into the non-local properties of the self-force. The Green function in Schwarzschild spacetime is expected to share certain key features with Nariai. In this way, the Nariai spacetime provides a fertile testing ground for developing insight into the non-local part of the self-force on black hole spacetimes.

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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