Quantum nature of the big bang: Improved dynamics

Abhay Ashtekar, Tomasz Pawlowski, Parampreet Singh
2006 Physical Review D  
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
more » ... 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.
doi:10.1103/physrevd.74.084003 fatcat:nyeyrfdllbc2de3rjiwl2qj7gi