Future instability of FLRW fluid solutions for linear equations of state $p=K\rho$ with $1/3<K<1$

Florian Beyer, Elliot Marshall, Todd A. Oliynyk

Using numerical methods, we examine the dynamics of nonlinear perturbations in the expanding time direction, under a Gowdy symmetry assumption, of FLRW fluid solutions to the Einst…