Loop quantum cosmology and singularities
arXiv:1703.10274 · doi:10.1038/s41598-017-06616-y
Abstract
Loop quantum gravity is believed to eliminate singularities such as the big bang and big crunch singularity. This belief is based on studies of so-called loop quantum cosmology which concerns symmetry-reduced models of quantum gravity. In this paper, the problem of singularities is analysed in the context of the Bohmian formulation of loop quantum cosmology. In this formulation there is an actual metric in addition to the wave function, which evolves stochastically (rather than deterministically as the case of the particle evolution in non-relativistic Bohmian mechanics). Thus a singularity occurs whenever this actual metric is singular. It is shown that in the loop quantum cosmology for a homogeneous and isotropic Friedmann-Lemaitre-Robertson-Walker space-time with arbitrary constant spatial curvature and cosmological constant, coupled to a massless homogeneous scalar field, a big bang or big crunch singularity is never obtained. This should be contrasted with the fact that in the Bohmian formulation of the Wheeler-DeWitt theory singularities may exist.
17 pages, no figures, LaTeX; v2 minor improvements
References in corpus (13)
- Quantum Nature of the Big Bang: Improved dynamics
- Quantum Nature of the Big Bang
- Quantum Nature of the Big Bang: An Analytical and Numerical Investigation
- Loop quantum cosmology of k=1 FRW models
- Loop quantum cosmology and the k = - 1 RW model
- Closed FRW model in Loop Quantum Cosmology
- Open FRW model in Loop Quantum Cosmology
- Consistent Probabilities in Wheeler-DeWitt Quantum Cosmology
- Physical time and other conceptual issues of QG on the example of LQC
- The Wheeler-DeWitt Quantization Can Solve the Singularity Problem
- Consistent Histories in Quantum Cosmology
- Quantum Hamiltonians and Stochastic Jumps
- Wheeler-DeWitt quantization and singularities
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