论文标题
宇宙加速度和大量重力结构的生长
Cosmic Acceleration and Growth of Structure in Massive Gravity
论文作者
论文摘要
我们在广义大型重力的框架中引入了宇宙学模型。该理论是非线性大型重力的延伸，在Stückelberg空间中具有断裂的翻译对称性。在最近的一项工作中，我们展示了宇宙学解决方案的存在，稳定地针对线性扰动。在本文中，我们基于先前的结果，研究了背景解决方案和线性扰动的演变。在背景层面，我们发现质量术语像一种液体一样，与状态相关的方程式$ w <-1 $在后期。按线性顺序，我们得出泊松方程。我们发现标量重力模式引起了各向异性应力，这在有效的牛顿常数和物质扰动的生长速度中对LCDM进行了修改。此外，我们研究了重力波的传播，发现张量模式获得了依赖时间的质量。
We introduce a cosmological model in the framework of Generalised Massive Gravity. This theory is an extension of non-linear massive gravity with a broken translation symmetry in the Stückelberg space. In a recent work, we showed the existence of cosmological solutions stable against linear perturbations. In the present paper, we build up on the previous result and study the evolution of the background solutions and the linear perturbations. At the background level, we find that the mass terms act like a fluid with time dependent equation of state $w < -1$ at late times. At linear order, we derive the Poisson's equation. We find that the scalar graviton mode invokes anisotropic stress, which brings a modification with respect to LCDM in the effective Newton's constant and the growth rate of matter perturbations. Moreover, we study the propagation of gravitational waves and find that the tensor modes acquire a time dependent mass.
