标题： 标量-流体理论中的爱因斯坦静态宇宙 显示英文标题

标题： The Einstein static universe in Scalar-Fluid theories

摘要： 最近提出了一种新的拉格朗日框架来描述相对论性完美流体与标量场之间的相互作用。 本文研究了这一新理论类中的爱因斯坦静态宇宙，这些理论被称为标量-流体力学理论。 通过在一次近似下推导相关的宇宙扰动方程，分析了静态解对于均匀和非均匀扰动的稳定性。 我们发现了一些对应于爱因斯坦静态宇宙的配置，它们对非均匀扰动是稳定的，但对均匀扰动是不稳定的。 这表明标量-流体力学理论可能在膨胀出现的宇宙场景中有应用。 显示英文摘要

摘要： A new Lagrangian framework has recently been proposed to describe interactions between relativistic perfect fluids and scalar fields. In this paper we investigate the Einstein static universe in this new class of theories, which have been named Scalar-Fluid theories. The stability of the static solutions to both homogeneous and inhomogeneous perturbations is analysed deriving the relevant cosmological perturbation equations at the linear order. We can find several configurations corresponding to an Einstein static universes which are stable against inhomogeneous perturbations, but unstable against homogeneous perturbations. This shows the possible applications of Scalar-Fluid theories to the inflationary emergent universe scenario.