Loop Quantum Cosmology: An Overview

Abstract

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. These results bear out the remarkable intuition that John Wheeler had. Discussion is organized at two levels. The the main text provides a bird's eye view of the subject that should be accessible to non-experts. Appendices address conceptual and technical issues that are often raised by experts in loop quantum gravity and string theory.

To appear in the Proceedings of the Bad Honef Workshop entitled \emph{Quantum Gravity: Challenges and Perspectives}, dedicated to the memory of John A. Wheeler

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Cited by in corpus (148)

• f(T) teleparallel gravity and cosmology
• Loop Quantum Cosmology: A Status Report
• A Short Review of Loop Quantum Gravity
• Loop quantum cosmology of Bianchi I models
• Cosmological and Solar System Consequences of f(R,T) Gravity Models
• Quantum Extension of the Kruskal Space-time
• Time and a physical Hamiltonian for quantum gravity
• Loop quantum cosmology of Bianchi type IX models
• Probability of Inflation in Loop Quantum Cosmology
• Towards Spinfoam Cosmology
• Loop quantum cosmology of Bianchi type II models
• Loop quantum cosmology and slow roll inflation
• A geometric perspective on singularity resolution and uniqueness in loop quantum cosmology
• Classical collapse to black holes and quantum bounces: A review
• Quantum cosmology from the de Broglie-Bohm perspective
• Physical evolution in Loop Quantum Cosmology: The example of vacuum Bianchi I
• Inflation in loop quantum cosmology: Dynamics and spectrum of gravitational waves
• Exotic singularities and spatially curved Loop Quantum Cosmology
• Finite-time Cosmological Singularities and the Possible Fate of the Universe
• Loop quantum gravity: the first twenty five years
• Observational issues in loop quantum cosmology
• Perfect discretization of reparametrization invariant path integrals
• Casting Loop Quantum Cosmology in the Spin Foam Paradigm
• How Far Are We from the Quantum Theory of Gravity?
• Anomaly-free perturbations with inverse-volume and holonomy corrections in Loop Quantum Cosmology
• The LQC evolution operator of FRW universe with positive cosmological constant
• Loop Quantum Cosmology and Spin Foams
• On the measure problem in slow roll inflation and loop quantum cosmology
• Cosmic recall and the scattering picture of Loop Quantum Cosmology
• Path Integrals and the WKB approximation in Loop Quantum Cosmology
• Big Bounce and inhomogeneities
• Duration of inflation and conditions at the bounce as a prediction of effective isotropic loop quantum cosmolog
• Loop quantum cosmology of k=1 FRW: A tale of two bounces
• Comparison of primordial tensor power spectra from the deformed algebra and dressed metric approaches in loop quantum cosmology
• A Hamiltonian Formulation of the BKL Conjecture
• Prescriptions in Loop Quantum Cosmology: A comparative analysis
• Coherent semiclassical states for loop quantum cosmology
• Perspectives on the dynamics in a loop quantum gravity effective description of black hole interiors
• A new look at loop quantum gravity
• Effective Dynamics from Coherent State Path Integral of Full Loop Quantum Gravity
• Quasinormal frequencies of self-dual black holes
• Emergent de Sitter epoch of the Loop Quantum Cosmos: a detailed analysis
• On the Semiclassical Limit of Loop Quantum Cosmology
• Primordial scalar power spectrum from the Euclidean Big Bounce
• Primordial black holes in loop quantum cosmology: The effect on the threshold
• Observational Exclusion of a Consistent Quantum Cosmology Scenario
• Anomaly-free vector perturbations with holonomy corrections in loop quantum cosmology
• Observing the Big Bounce with Tensor Modes in the Cosmic Microwave Background: Phenomenology and Fundamental LQC Parameters
• Primordial tensor power spectrum in holonomy corrected Omega-LQC
• Non-singular Ekpyrotic/Cyclic model in Loop Quantum Cosmology
• Nonsingular bouncing cosmology in general relativity: physical analysis of the spacetime defect
• Derivations of group rings
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• Detailed investigation of the duration of inflation in loop quantum cosmology for a Bianchi-I universe with different inflaton potentials and initial conditions
• The Wheeler-DeWitt Quantization Can Solve the Singularity Problem
• Criteria for the determination of time dependent scalings in the Fock quantization of scalar fields with a time dependent mass in ultrastatic spacetimes
• Quantum evolution of black hole initial data sets: Foundations
• Cosmological Coherent State Expectation Values in LQG I. Isotropic Kinematics
• Conditional symmetries in axisymmetric quantum cosmologies with scalar fields and the fate of the classical singularities
• Triangulated Loop Quantum Cosmology: Bianchi IX and inhomogenous perturbations
• Simple model for quantum general relativity from loop quantum gravity
• Gauss-Bonnet modified gravity models with bouncing behavior
• Modified general relativity as a model for quantum gravitational collapse
• Effective Dynamics in Bianchi Type II Loop Quantum Cosmology
• A comparison between Jordan and Einstein frames of Brans-Dicke gravity a la loop quantum cosmology
• Loop quantum Brans-Dicke cosmology
• Building non commutative spacetimes at the Planck length for Friedmann flat cosmologies
• Improved ($\bar{\mu }$-Scheme) Effective Dynamics of Full Loop Quantum Gravity
• Exploring the Hubble tension with a late time Modified Gravity scenario
• Interplay between curvature and Planck-scale effects in astrophysics and cosmology
• Stability analysis of an autonomous system in loop quantum cosmology
• Path integral polymer propagator of relativistic and non-relativistic particles
• Effective dynamics of the hybrid quantization of the Gowdy T^3 universe
• A phenomenology analysis of the tachyon warm inflation in loop quantum cosmology
• Effective constrained polymeric theories and their continuum limit
• Observational hints on the Big Bounce
• Spinfoam Cosmology: quantum cosmology from the full theory
• Implications of the gauge-fixing in Loop Quantum Cosmology
• Vacuum fluctuation, micro-cyclic "universes" and the cosmological constant problem
• The emergence of Special and Doubly Special Relativity
• Exhaustive investigation of the duration of inflation in effective anisotropic loop quantum cosmology
• Cosmological models in Weyl geometrical scalar-tensor theory
• Reduced Phase Space Quantization of Black Holes: Path Integrals, and Effective Dynamics
• Coherent State Functional Integral in Loop Quantum Cosmology: Alternative Dynamics
• QFT on quantum spacetime: a compatible classical framework
• Path Integrals and Alternative Effective Dynamics in Loop Quantum Cosmology
• Inverse problem: Reconstruction of modified gravity action in Palatini formalism by Supernova Type Ia data
• Higher dimensional Loop Quantum Cosmology
• Unimodular Loop Quantum Cosmology
• Phase space analysis of the bouncing universe with stringy effects
• Some surprising implications of background independence in canonical quantum gravity
• On the stability of Einstein static universe at background level in massive bigravity
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• Singularity resolution from polymer quantum matter
• Behavior of the Universe anisotropy in a big-bounce cosmology
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• Stable, non-singular bouncing universe with only a scalar mode
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• What kind of science is cosmology?
• Dynamical behavior of interacting dark energy in loop quantum cosmology
• Modified Friedmann equation and survey of solutions in effective Bianchi-I loop quantum cosmology
• Minimal Coupling and Attractors
• Our Universe from the cosmological constant
• Loop quantum gravity and cosmological constant
• Bianchi type-I string cosmological model in the presence of a magnetic field: classical versus loop quantum cosmology approaches
• Discreteness of time in the evolution of the universe
• Quantum geometry and effective dynamics of Janis-Newman-Winicour singularities
• Could Planck Star Remnants be Dark Matter?
• Big Bounce in Dipole Cosmology
• Semiclassical and quantum behavior of the Mixmaster model in the polymer approach
• Phenomenology of effective geometries from quantum gravity
• Loop quantum modified gravity and its cosmological application
• Herglotz Action for Homogeneous Cosmology
• An Inhomogeneous Space-Time Patching Model Based on a Nonlocal and Nonlinear Schrodinger Equation
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• Alternative $k=-1$ loop quantum cosmology
• $\Lambda CDM$ periodic cosmology
• Is there a super-selection rule in quantum cosmology?
• An Approach to Loop Quantum Cosmology Through Integrable Discrete Heisenberg Spin Chains
• Internal time, test clocks and singularity resolution in dust-filled quantum cosmology
• Does Quantum Cosmology Predict the Age of the Universe?
• Effective LQC model for k=+1 isotropic cosmologies from spatial discretisations
• On Special Re-quantization of a Black Hole
• Cosmological particle production in quantum gravity
• Quantum Mechanics from General Relativity and the Quantum Friedmann Equation
• Loop quantum cosmological model from ADM Hamiltonian
• Spacetime Quanta? : The Discrete Spectrum of a Quantum Spacetime Four-Volume Operator in Unimodular Loop Quantum Cosmology
• Cyclic spacetimes through singularity scattering maps. Plane-symmetric gravitational collisions
• Cosmic tango between the very small and the very large: Addressing CMB anomalies through Loop Quantum Cosmology
• Does Cosmology require Hermiticity in Quantum Mechanics?
• Consistent Probabilities in Perfect Fluid Quantum Universes
• Effective LQG-inspired dynamics of a thin shell and the fate of a collapsing star
• Thermodynamics properties of the dark energy in loop quantum cosmology
• Gaussian Planck Relics are Ruled-Out as Dark Matter by LIGO
• Higher-dimensional quantum-corrected Oppenheimer-Snyder model with a cosmological constant
• (Anti-)BRST Symmetries in FLRW Model: Supervariable Approach
• Effective dynamics of Janis-Newman-Winicour spacetime