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arXiv · 2304.06760

Quantum gravitational non-singular tunneling wavefunction proposal

Meysam Motaharfar·Parampreet Singh
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Abstract

It was recently shown that tunneling wavefunction proposal is consistent with loop quantum geometry corrections including both holonomy and inverse scale factor corrections in the gravitational part of a spatially closed isotropic model with a positive cosmological constant. However, in presence of an inflationary potential the initial singularity is kinetic dominated and the effective minisuperspace potential again diverges at zero scale factor. Since the wavefunction in loop quantum cosmology cannot increase towards the zero scale factor, the tunneling wavefunction seems incompatible. We show that consistently including inverse scale factor modifications in scalar field Hamiltonian changes the effective potential into a barrier potential allowing the tunneling proposal. We also discuss a potential quantum instability of the cyclic universe resulting from tunneling.

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Meysam Motaharfar, Parampreet Singh. 2023-04-13. Quantum gravitational non-singular tunneling wavefunction proposal. https://doi.org/10.3390/ecu2023-14101

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