79 citations · 224 across the 10 of their papers we have counts for
8 papers · 1 filter
Spherically symmetric Einstein-aether perfect fluid models
Alan A. Coley, Genly Leon, Patrik Sandin +1
We investigate spherically symmetric cosmological models in Einstein-aether theory with a tilted (non-comoving) perfect fluid source. We use a 1+3 frame formalism and adopt the com…
Stability of Einstein-Aether Cosmological Models
Patrik Sandin, Bassemah Alhulaimi, Alan Coley
We use a dynamical systems analysis to investigate the future behaviour of Einstein-Aether cosmological models with a scalar field coupling to the expansion of the aether and a non…
The initial singularity of ultrastiff perfect fluid spacetimes without symmetries
J. Mark Heinzle, Patrik Sandin
We consider the Einstein equations coupled to an ultrastiff perfect fluid and prove the existence of a family of solutions with an initial singularity whose structure is that of ex…
Future asymptotics of tilted Bianchi type II cosmologies
Sigbjorn Hervik, Woei Chet Lim, Patrik Sandin +1
In this paper we study the future asymptotics of spatially homogeneous Bianchi type II cosmologies with a tilted perfect fluid with a linear equation of state. By means of Hamilton…
Perfect fluids and generic spacelike singularities
Patrik Sandin, Claes Uggla
We present the conformally 1+3 Hubble-normalized field equations together with the general total source equations, and then specialize to a source that consists of perfect fluids w…
Tilted two-fluid Bianchi type I models
Patrik Sandin
In this paper we investigate expanding Bianchi type I models with two tilted fluids with the same linear equation of state, characterized by the equation of state parameter w. Indi…