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arXiv · 1004.4947

A Radiation Bounce from the Lee-Wick Construction?

Johanna Karouby·Robert Brandenberger
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Abstract

It was recently realized that matter modeled by the scalar field sector of the Lee-Wick Standard Model yields, in the context of a homogeneous and isotropic cosmological background, a bouncing cosmology. However, bouncing cosmologies induced by pressure-less matter are in general unstable to the addition of relativistic matter (i.e. radiation). Here we study the possibility of obtaining a bouncing cosmology if we add not only radiation, but also its Lee-Wick partner, to the matter sector. We find that, in general, no bounce occurs. The only way to obtain a bounce is to choose initial conditions with very special phases of the radiation field and its Lee-Wick partner.

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Johanna Karouby, Robert Brandenberger. 2010-04-28. A Radiation Bounce from the Lee-Wick Construction?. https://doi.org/10.1103/physrevd.82.063532

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