Perturbations of the Lambda-CDM model in a dynamical systems perspective

Understand

The observational success and simplicity of the $\Lambda$CDM model, and the explicit analytic perturbations thereof, set the standard for any alternative cosmology.

• It therefore serves as a comparison ground and as a test case for methods which can be extended and applied to other cosmological models.
• In this paper we introduce dynamical systems and methods to describe linear scalar and tensor perturbations of the $\Lambda$CDM model, which serve as pedagogical examples that show the global illustrative powers of dynamical systems in the context of cosmological perturbations.
• We also study the asymptotic properties of the shear and Weyl tensors and discuss the validity of the perturbations as approximations to the Einstein field equations.