We compute the modified friction coefficient controlling the propagation of tensor metric perturbations in the context of a generalized cosmological scenario based on a theory of gravity with quadratic curvature corrections. In such a context we discuss the differences between gravitational and electromagnetic luminosity distance, as well as the differences with the standard results based on the Einstein equations. We present numerical estimates of the modified luminosity distance on the cosmic redshift scale typical of Supernovae and standard sirens.

中文翻译：

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在简单的二次重力模型中比较引力波和电磁信号的光度距离

我们在基于具有二次曲率校正的重力理论的广义宇宙学场景中计算控制张量度量扰动传播的修正摩擦系数。在这样的背景下，我们讨论了引力和电磁光度距离之间的差异，以及与基于爱因斯坦方程的标准结果的差异。我们提供了超新星和标准警报器典型的宇宙红移尺度上修正光度距离的数值估计。