标题： 一般FRW宇宙学中的因果摄动理论I：能量动量守恒和匹配条件 显示英文标题

标题： Causal perturbation theory in general FRW cosmologies I: energy momentum conservation and matching conditions

摘要： 我们描述了在具有因果源项的一般FRW背景下相对论扰动理论中的能量-动量守恒问题，例如宇宙缺陷网络的存在。 我们在弯曲FRW宇宙中提供了一个线性能量-动量伪张量的定义，并使用亥姆霍兹方程的特征函数对其进行分解。 我们还构造了这些时空共形几何的守恒矢量密度，并将其与我们的伪张量联系起来，证明了这两种方法的等价性。 我们还将这些技术与残余规范自由度在早期相变处建立匹配条件的作用联系起来，我们可以用伪张量的分量来表达这些匹配条件。 该形式体系在子视界和超视界尺度上都简洁且几何上合理，从而将现有工作扩展到一个物理上（和数值上）有用的背景中。 显示英文摘要

摘要： We describe energy--momentum conservation in relativistic perturbation theory in general FRW backgrounds with causal source terms, such as the presence of cosmic defect networks. We provide a prescription for a linear energy--momentum pseudo-tensor in a curved FRW universe, decomposing it using eigenfunctions of the Helmholtz equation. We also construct conserved vector densities for the conformal geometry of these spacetimes and relate these to our pseudo-tensor, demonstrating the equivalence of these two approaches. We also relate these techniques to the role played by residual gauge freedom in establishing matching conditions at early phase transitions, which we can express in terms of components of our pseudo-tensor. This formalism is concise and geometrically sound on both sub- and superhorizon scales, thus extending existing work to a physically (and numerically) useful context.