论文标题
在空间协变重力：退化条件和模拟配方
Spatially covariant gravity: Degeneracy condition and mimetic formulation
论文作者
论文摘要
我们只对空间对称性进行空间协变量进行扰动分析，其中拉格朗日包括动态失去功能和空间曲率和外部曲率的耦合项。我们表明，该理论传播了2个标量自由度，只要动力学术语是堕落的，它就会在线性顺序传播单个标量模式。然后，我们计算标量和张量功率谱。最后，我们研究了在空间协变重力存在下模拟重力的宇宙学扰动。原始的空间协变理论传播了2个标量的自由度，并且在添加模仿约束后将仅传播一个标量自由度。
We make a perturbative analysis of spatially covariant gravity only respecting spatial symmetries, of which the Lagrangian includes the dynamic lapse function and the coupling term of spatial curvature and extrinsic curvature. We show that the theory propagates 2 scalar degrees of freedom, as long as the kinetic terms are degenerate, it propagates a single scalar mode at the linear order. Then we calculate the scalar and tensor power spectra. Finally, we study cosmological perturbations in mimetic gravity in the presence of spatially covariant gravity. The original spatially covariant theory propagates 2 scalar degrees of freedom, and it will propagate only one scalar degree of freedom after adding the mimetic constraint.
