scispace - formally typeset
Open AccessJournal ArticleDOI

The status of quantum geometry in the dynamical sector of loop quantum cosmology

TLDR
In this paper, the quantum geometry operators of LQC in both the kinematical and the physical Hilbert spaces of solutions to the quantum constraints are derived, and quantum geometry can be used to characterize the physical solutions, and the operators of quantum geometry preserve many of their kinematics.
Abstract
This paper is motivated by the recent papers by Dittrich and Thiemann and, respectively, Rovelli discussing the status of quantum geometry in the dynamical sector of quantum geometry. Since the papers consider model examples, we also study the issue in the case of an example, namely on the loop quantum cosmology model of a space-isotropic universe. We derive the Rovelli–Thiemann–Dittrich partial observables corresponding to the quantum geometry operators of LQC in both Hilbert spaces: the kinematical one and the physical Hilbert space of solutions to the quantum constraints. We find that quantum geometry can be used to characterize the physical solutions, and the operators of quantum geometry preserve many of their kinematical properties.

read more

Citations
More filters
Journal ArticleDOI

Loop Quantum Cosmology: A Status Report

TL;DR: Loop quantum cosmology (LQC) as mentioned in this paper is the result of applying principles of loop quantum gravity to cosmological settings, where quantum geometry creates a brand new repulsive force which is totally negligible at low spacetime curvature but rises very rapidly in the Planck regime, overwhelming the classical gravitational attraction.
Journal ArticleDOI

Loop Quantum Cosmology: An Overview

TL;DR: A brief overview of loop quantum cosmology of homogeneous isotropic models is presented with emphasis on the origin of and subtleties associated with the resolution of big bang and big crunch singularities as discussed by the authors.
Journal ArticleDOI

Loop Quantum Cosmology: An Overview

TL;DR: A brief overview of loop quantum cosmology of homogeneous isotropic models is presented with emphasis on the origin of and subtleties associated with the resolution of big bang and big crunch singularities.
Journal ArticleDOI

Cosmic recall and the scattering picture of Loop Quantum Cosmology

TL;DR: In this article, the global dynamics of a homogeneous universe in loop quantum cosmology is viewed as a scattering process of its geometrodynamical equivalent, and a flexible (easy to generalize) and not restricted just to exactly solvable models method of verifying the preservation of the semiclassicality through the bounce is proposed.
Journal ArticleDOI

Loop Quantum Cosmology: A Status Report

TL;DR: An overview of the current state of the art in loop quantum cosmology for three sets of audiences is given in this article, including young researchers interested in entering this area, the quantum gravity community in general, and cosmologists who wish to apply loop quantum Cosmology to probe modifications in the standard paradigm of the early universe.
References
More filters
Journal ArticleDOI

Background independent quantum gravity: A Status report

TL;DR: Loop quantum gravity as discussed by the authors is a background-independent, non-perturbative approach to the problem of unification of general relativity and quantum physics, based on a quantum theory of geometry.
Journal ArticleDOI

Discreteness of area and volume in quantum gravity

TL;DR: In this article, the authors studied the spectrum of the volume in nonperturbative quantum gravity, and showed that the spectrum can be computed by diagonalizing finite dimensional matrices, which can be seen as a generalization of the spin networks.
Journal ArticleDOI

Quantum Nature of the Big Bang: Improved dynamics

TL;DR: In this article, an improved Hamiltonian constraint operator is introduced in loop quantum cosmology for the isotropic model with a massless scalar field and the big bang is replaced by a quantum bounce.
Journal ArticleDOI

Quantum Nature of the Big Bang

TL;DR: The known results on the resolution of the big-bang singularity in loop quantum cosmology are significantly extended, and unlike in other approaches the quantum evolution is deterministic across the deep Planck regime.
Journal ArticleDOI

Loop Quantum Cosmology

TL;DR: In this paper, an application of loop quantum cosmology to homogeneous systems, which removes classical singularities, is presented, where the main effects are introduced into effective classical equations, which allow one to avoid the interpretational problems of quantum theory.
Related Papers (5)