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arXiv · 1808.01744

The no-boundary wave function for loop quantum cosmology

Suddhasattwa Brahma·Dong-han Yeom
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Abstract

Proposing smooth initial conditions is one of the most important tasks in quantum cosmology. On the other hand, the low-energy effective action, appearing in the semiclassical path integral, can get nontrivial quantum corrections near classical singularities due to specific quantum gravity proposals. In this article, we combine the well-known no-boundary proposal for the wavefunction of the universe with quantum modifications coming from loop quantum cosmology (LQC). Remarkably, we find that the restriction of a `slow-roll' type potential in the original Hartle-Hawking proposal is considerably relaxed due to quantum geometry regularizations. Interestingly, the same effects responsible for singularity-resolution in LQC also end up expanding the allowed space of smooth initial conditions leading to an inflationary universe.

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Suddhasattwa Brahma, Dong-han Yeom. 2018-08-06. The no-boundary wave function for loop quantum cosmology. https://doi.org/10.1103/physrevd.98.083537

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