标题： 暴胀在一般协变规范中的光子传播子 显示英文标题

标题： Photon propagator for inflation in the general covariant gauge

摘要： 在规范协变规范下，考虑了幂律暴胀中的光子传播子，是在正则量子化形式中进行的。 协变规范下的光子模函数比其标量对应物要复杂得多，除非选择我们称为简单协变规范的规范固定参数。 我们显式地构造了简单协变规范下的位置空间光子传播子，并发现结果比其标量对应物复杂得多。 这是因为需要显式地反转作用于标量传播子上的拉普拉斯算子，这导致了阿佩尔的第四函数。 我们的传播子正确地再现了德西特空间和平坦空间极限。 我们使用这个传播子来计算两个简单的可观测量：非共点场强-场强关联函数和能量-动量张量，两者都得到了一致的结果。 作为我们计算的副产品，我们还给出了任意维度下幂律暴胀中库仑规范传播子的精确表达式。 显示英文摘要

摘要： Photon propagator for power-law inflation is considered in the general covariant gauges within the canonical quantization formalism. Photon mode functions in covariant gauges are considerably more complicated than their scalar counterparts, except for the special choice of the gauge-fixing parameter we call the simple covariant gauge. We explicitly construct the position space photon propagator in the simple covariant gauge, and find the result considerably more complicated than its scalar counterpart. This is because of the need for explicitly inverting the Laplace operator acting on the scalar propagator, which results in Appell's fourth function. Our propagator correctly reproduces the de Sitter and flat space limits. We use this propagator to compute two simple observables: the off-coincident field strength-field strength correlator and the energy-momentum tensor, both of which yield consistent results. As a spinoff of our computation we also give the exact expression for the Coulomb gauge propagator in power-law inflation in arbitrary dimensions.