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We present a novel cosmological model in which scalar field matter in abiaxial Bianchi IX geometry leads to a non-singular `pancaking' solution: thehypersurface volume goes to zero instantaneously at the `Big Bang', but allphysical quantities, such as curvature invariants and the matter energy densityremain finite, and continue smoothly through the Big Bang. We demonstrate thatthere exist geodesics extending through the Big Bang, but that there are alsoincomplete geodesics that spiral infinitely around a topologically closedspatial dimension at the Big Bang, rendering it, at worst, a quasi-regularsingularity. The model is thus reminiscent of the Taub-NUT vacuum solution inthat it has biaxial Bianchi IX geometry and its evolution exhibits adimensionality reduction at a quasi-regular singularity; the two models are,however, rather different, as we will show in a future work. Here weconcentrate on the cosmological implications of our model and show how thescalar field drives both isotropisation and inflation, thus raising thequestion of whether structure on the largest scales was laid down at a timewhen the universe was still oblate (as also suggested by Pitrou et al andContaldi et al). We also discuss the stability of our model to smallperturbations around biaxiality and draw an analogy with cosmologicalperturbations. We conclude by presenting a separate, bouncing solution, whichgeneralises the known bouncing solution in closed FRW universes.

An anisotropic, non-singular early universe model leading to a realistic cosmology