139 citations · 772 across the 25 of their papers we have counts for
21 papers · 1 filter
Quintessence from a state space perspective
Artur Alho, Claes Uggla, John Wainwright
We use dynamical systems methods to study quintessence models in a spatially flat and isotropic spacetime with matter and a scalar field with potentials for which …
Dynamical systems in perturbative scalar field cosmology
Artur Alho, Claes Uggla, John Wainwright
We derive a new \emph{regular} dynamical system on a 3-dimensional \emph{compact} state space describing linear scalar perturbations of spatially flat Robertson-Walker geometries f…
Perturbations of the Lambda-CDM model in a dynamical systems perspective
Artur Alho, Claes Uggla, John Wainwright
The observational success and simplicity of the CDM model, and the explicit analytic perturbations thereof, set the standard for any alternative cosmology. It therefore serves a…
Second order cosmological perturbations: new conserved quantities and the general solution at super-horizon scale
Claes Uggla, John Wainwright
The study of long wavelength scalar perturbations, in particular the existence of conserved quantities when the perturbations are adiabatic, plays an important role in e.g. inflati…
The general solution at large scale for second order perturbations in a scalar field dominated universe
Claes Uggla, John Wainwright
In this paper we consider second order perturbations of a flat Friedmann-Lemaître universe whose stress-energy content is a single minimally coupled scalar field with an arbitrary…
Dynamics of cosmological perturbations at first and second order
Claes Uggla, John Wainwright
In this paper we give five gauge-invariant systems of governing equations for first and second order scalar perturbations of flat Friedmann-Lemaître universes that are minimal in t…