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arXiv · 2604.00297

Big bang stability and isotropisation for the Einstein-scalar field equations in the ekpyrotic regime

Florian Beyer·David Garfinkle·James Isenberg·Todd A. Oliynyk
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Abstract

It has been shown that, in spacetime dimensions $n\geq 3$, that the Kasner-scalar field solutions to the Einstein-scalar fields equations with potential $V_0 e^{-s \phi}$, where $s s_c$ and $V_0<0$. Such scalar field potentials are known in the literature as \textit{ekpyrotic}. In particular, we prove that the FLRW solutions to the Einstein-scalar field equations are nonlinearly stable to the past and terminate at a quiescent, crushing AVTD big bang singularity. A distinguishing property of these perturbed spacetimes is that they isotropise towards the big bang.

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Florian Beyer, David Garfinkle, James Isenberg, Todd A. Oliynyk. 2026-03-31. Big bang stability and isotropisation for the Einstein-scalar field equations in the ekpyrotic regime. https://arxiv.org/abs/2604.00297

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