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arXiv · 2204.01771

Quantum resolution of the cosmological singularity without new physics

Steffen Gielen·João Magueijo
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Abstract

We study a quantum Hot Big Bang in the connection representation, with a matter constant of motion m whose conjugate defines time. Superpositions in m induce a unitary inner product. The wavefunction reveals a resolution of the singularity problem without new physics or supplementary boundary conditions. Backtracking in time, the probability peak eventually halts at a maximum curvature, its height dropping thereafter while a symmetric contracting peak rises. The Big Bang is replaced by a superposition of contracting and expanding regular Universes. We contrast these findings with the situation in the metric representation, where boundary conditions at the singularity are needed for unitary evolution.

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Steffen Gielen, João Magueijo. 2023-02-22. Quantum resolution of the cosmological singularity without new physics. https://doi.org/10.1209/0295-5075%2Facbc48

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