论文标题
宇宙发展中的宇宙进化
Cosmic evolution in novel-Gauss Bonnet Gravity
论文作者
论文摘要
在这篇简短的论文中，我们研究了新型高斯重力重力可能会在四个时空维度中引起宇宙的宇宙演化。我们首先考虑了通用的Friedmann-Lema-Robertson-Walker（FLRW）指标，尊重任意时空维度$ D $中的同质性和各向同性。度量取决于两个函数：比例因子和失效。将此度量插入新型的爱因斯坦 - 加斯 - 鲍涅特（EGB）重力动作中，按零件进行集成，然后按$ d \ to4 $的限制为我们提供四个时空维度的动态动作，以实现尺度因子和失误。高斯 - 骨网耦合的特殊重新缩放为$ d-4 $，从而在理论的作用中产生了非平凡的贡献。在本文中，我们研究了这一行动。我们研究了比例因子的动力学和空旷宇宙中的衰落行为（无论如何）。由于问题的复杂性，我们研究了高斯 - 骨网耦合和方程式系统的一阶理论。我们将一阶校正计算为空宇宙的壳动作，并发现其符号与领先顺序部分相反。我们讨论它的后果。
In this short paper we investigate any non-trivial effect the novel Gauss-Bonnet gravity may give rise in the cosmic evolution of the Universe in four spacetime dimensions. We start by considering a generic Friedmann-Lemaître-Robertson-Walker (FLRW) metric respecting homogeneity and isotropicity in arbitrary space-time dimension $D$. The metric depends on two functions: scale factor and lapse. Plugging this metric in novel Einstein-Gauss-Bonnet (EGB) gravity action, doing an integration by parts and then take the limit of $D\to4$ give us a dynamical action in four spacetime dimensions for scale factor and lapse. The peculiar rescaling of Gauss-Bonnet coupling by factor of $D-4$ results in a non-trivial contribution in the action of the theory. In this paper we study this action. We investigate the dynamics of scale-factor and behavior of lapse in an empty Universe (no matter). Due to complexity of the problem we study the theory to first order in Gauss-Bonnet coupling and solve system of equation to the first order. We compute the first order correction to the on-shell action of the empty Universe and find that its sign is opposite of the leading order part. We discuss it consequences.
