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Quantum Nature of the Big Bang

Abhay Ashtekar·Tomasz Pawlowski·Parampreet Singh
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Abstract

Some long standing issues concerning the quantum nature of the big bang are resolved in the context of homogeneous isotropic models with a scalar field. Specifically, the known results on the resolution of the big bang singularity in loop quantum cosmology are significantly extended as follows: i) the scalar field is shown to serve as an internal clock, thereby providing a detailed realization of the `emergent time' idea; ii) the physical Hilbert space, Dirac observables and semi-classical states are constructed rigorously; iii) the Hamiltonian constraint is solved numerically to show that the big bang is replaced by a big bounce. Thanks to the non-perturbative, background independent methods, unlike in other approaches the quantum evolution is deterministic across the deep Planck regime.

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Abhay Ashtekar, Tomasz Pawlowski, Parampreet Singh. 2006-04-06. Quantum Nature of the Big Bang. https://doi.org/10.1103/physrevlett.96.141301

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