3 papers
gr-qc2026
Big bang stability and isotropisation for the Einstein-scalar field equations in the ekpyrotic regime
Florian Beyer, David Garfinkle, James Isenberg +1
It has been shown that, in spacetime dimensions , that the Kasner-scalar field solutions to the Einstein-scalar fields equations with potential , where $s<s…
math.AP2025
A critical threshold for the cosmological Euler-Poisson system
David Fajman, Maciej Maliborski, Maximilian Ofner +2
We consider the gravitational Euler-Poisson system with a linear equation of state on an expanding cosmological model of the Universe. The expansion of the spatial sections introdu…
gr-qc2025
Stability of fluids in spacetimes with decelerated expansion
David Fajman, Maximilian Ofner, Todd Oliynyk +1
We prove the nonlinear stability of homogeneous barotropic perfect fluid solutions in fixed cosmological spacetimes undergoing decelerated expansion. The results hold provided a sp…