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arXiv · 0812.3552

Tachyon field in loop quantum cosmology: An example of traversable singularity

Li-Fang Li·Jian-Yang Zhu
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Abstract

Loop quantum cosmology (LQC) predicts a nonsingular evolution of the universe through a bounce in the high energy region. But LQC has an ambiguity about the quantization scheme. Recently, the authors in [Phys. Rev. D 77, 124008 (2008)] proposed a new quantization scheme. Similar to others, this new quantization scheme also replaces the big bang singularity with the quantum bounce. More interestingly, it introduces a quantum singularity, which is traversable. We investigate this novel dynamics quantitatively with a tachyon scalar field, which gives us a concrete example. Our result shows that our universe can evolve through the quantum singularity regularly, which is different from the classical big bang singularity. So this singularity is only a week singularity.

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Li-Fang Li, Jian-Yang Zhu. 2008-12-18. Tachyon field in loop quantum cosmology: An example of traversable singularity. https://doi.org/10.1103/physrevd.79.124011

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