2011/04/30 by Babak Vakili · 1 citation
Physics and Astronomy · #Classical mechanics #Cosmology #Cosmology and Gravitation Theories #Loop quantum cosmology #Mathematical physics #Minisuperspace #Noncommutative and Quantum Gravity Theories #Physics #Quantum #Quantum Mechanics and Applications #Quantum cosmology #Quantum gravity #Quantum mechanics #Theoretical physics #Wheeler–DeWitt equation #astro-ph.CO #gr-qc #hep-th
paper · pdf · doi:10.1103/physrevd.83.103505
published as Phys.Rev.D83:103505,2011 · 15 pages, 10 figures, typos corrected, Refs. added
openalex publication_date 2011/05/03 · arxiv created 2011/05/04 · arxiv updated 2015/03/18 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We study the classical and quantum models of a flat Friedmann-Robertson-Walker space-time, coupled to a perfect fluid, in the context of the consensus and a gauge-fixed Lagrangian frameworks. It is shown that, either in the usual or in the gauge-fixed actions, the evolution of the Universe based on the classical cosmology represents a late time power law expansion, coming from a big-bang singularity in which the scale factor goes to zero for the standard matter, and tending towards a big-rip singularity in which the scale factor diverges for the phantom fluid. We then employ the familiar canonical quantization procedure in the given cosmological setting to find the cosmological wave functions in the corresponding minisuperspace. Using a gauge-fixed (reduced) Lagrangian, we show that it may lead to a Schr"odinger equation for the quantum-mechanical description of the model under consideration, the eigenfunctions of which can be used to construct the time dependent wave function of the Universe. We use the resulting wave function in order to investigate the possibility of the avoidance of classical singularities due to quantum effects by means of the many-worlds and ontological interpretation of quantum cosmology.