Geodesically complete nondiagonal inhomogeneous cosmological solutions in dilatonic gravity with a stiff perfect fluid

TL;DR

This paper presents new inhomogeneous cosmological solutions in scalar-tensor theories that are free of singularities and are geodesically complete, expanding understanding of non-singular universe models.

Contribution

It introduces a class of nondiagonal inhomogeneous solutions in scalar-tensor gravity with a stiff fluid, which are free of singularities and geodesically complete.

Findings

Solutions have no big-bang or curvature singularities.

Dilaton field and energy density are regular everywhere.

Solutions are geodesically complete.

Abstract

New nondiagonal $G_{2}$ inhomogeneous cosmological solutions are presented in a wide range of scalar-tensor theories with a stiff perfect fluid as a matter source. The solutions have no big-bang singularity or any other curvature singularities. The dilaton field and the fluid energy density are everywhere regular, too. The geodesic completeness of the solutions is investigated.