Quantum Nature of the Big Bang: Improved dynamics

2006/07/31 by Abhay Ashtekar, Tomasz Pawlowski, Parampreet Singh · 6 citations
Physics and Astronomy · #gr-qc #hep-th

paper · pdf · doi:10.1103/physrevd.74.084003

published as Phys.Rev.D74:084003,2006 · Typos corrected. Revised version to appear in Physical Review D

arxiv created 2006/08/30 · arxiv updated 2009/12/01

Abstract

An improved Hamiltonian constraint operator is introduced in loop quantum cosmology. Quantum dynamics of the spatially flat, isotropic model with a massless scalar field is then studied in detail using analytical and numerical methods. The scalar field continues to serve as `emergent time', the big bang is again replaced by a quantum bounce, and quantum evolution remains deterministic across the deep Planck regime. However, while with the Hamiltonian constraint used so far in loop quantum cosmology the quantum bounce can occur even at low matter densities, with the new Hamiltonian constraint it occurs only at a Planck-scale density. Thus, the new quantum dynamics retains the attractive features of current evolutions in loop quantum cosmology but, at the same time, cures their main weakness.

Cited by

• Quantum Big Bounce in Wheeler-DeWitt scattering theory: Ekpyrotic and LQC-like transitions
• Does Quantum Cosmology Predict the Age of the Universe?
• Circular orbits and accretion disk around a deformed-Schwarzschild black hole in loop quantum gravity
• Hawking evaporation and the fate of black holes in loop quantum gravity
• Asymmetric Quantum Oppenheimer-Snyder Collapse
• A loop quantization of the marginally bound Lemaître-Tolman-Bondi dust model