Loop quantum gravity and cosmological constant

Abstract

An one-parameter regularization freedom of the Hamiltonian constraint for loop quantum gravity is analyzed. The corresponding spatially flat, homogenous and isotropic model includes the two well-known models of loop quantum cosmology as special cases. The quantum bounce nature is tenable in the generalized cases. For positive value of the regularization parameter, the effective Hamiltonian leads to an asymptotic de-Sitter branch of the Universe connecting to the standard Friedmann branch by the quantum bounce. Remarkably, by suitably choosing the value of the regularization parameter, the observational cosmological constant can emerge at large volume limit from the effect of quantum gravity, and the effective Newtonian constant satisfies the experimental restrictions in the meantime.

6 pages, 1 figure; v2, accepted by PLB

References in corpus (7)

• Dark Energy and the Accelerating Universe
• Quantum Nature of the Big Bang: Improved dynamics
• Quantum Nature of the Big Bang
• Loop Quantum Cosmology: An Overview
• Extension of loop quantum gravity to $f(R)$ theories
• Effective Scenario of Loop Quantum Cosmology
• Effective Dynamics from Coherent State Path Integral of Full Loop Quantum Gravity

Cited by in corpus (7)

• Quantum Oppenheimer-Snyder and Swiss Cheese models
• Inflation, phase transitions and the cosmological constant
• Alternative $k=-1$ loop quantum cosmology
• Quantum Oppenheimer-Snyder models in loop quantum cosmology with Lorentz term
• Loop quantum cosmological model from ADM Hamiltonian
• Effective Dynamics of Loop Quantum Kaluza-Klein Cosmology
• Unitary evolution and cosmic acceleration in Loop Quantum Cosmology