A Short Review of Loop Quantum Gravity

Abstract

An outstanding open issue in our quest for physics beyond Einstein is the unification of general relativity (GR) and quantum physics. Loop quantum gravity (LQG) is a leading approach toward this goal. At its heart is the central lesson of GR: Gravity is a manifestation of spacetime geometry. Thus, the approach emphasizes the quantum nature of geometry and focuses on its implications in extreme regimes -- near the big bang and inside black holes -- where Einstein's smooth continuum breaks down. We present a brief overview of the main ideas underlying LQG and highlight a few recent advances. This report is addressed to non-experts.

35 pages, 6 figures; Key Issues Review commissioned by the Journal

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Cited by in corpus (136)

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• Emergent Cosmology from Quantum Gravity in the Lorentzian Barrett-Crane Tensorial Group Field Theory Model
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• Observational signature of Lorentz violation in acceleration radiation
• Schwarzschild Black Hole Surrounded by Perfect Fluid Dark Matter in the presence of Quintessence Matter Field
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• Developed Method. Interactions and their quantum picture
• Topologically Charged Holonomy corrected Schwarzschild black hole lensing
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• Holographic maps from quantum gravity states as tensor networks
• Polymer dynamics of isotropic universe in Ashtekar and in volume variables
• Unveiling the Importance of Nonshortest Paths in Quantum Networks
• Suppression of spacetime singularities in quantum gravity
• Light deflection and gravitational lensing effects inspired by loop quantum gravity
• Big Bang Singularity Resolution In Quantum Cosmology
• Wheeler-DeWitt equation and the applicability of crypto-Hermitian interaction representation in quantum cosmology
• Scale-invariance at the core of quantum black holes
• One-loop effective action of the IKKT model for cosmological backgrounds
• Is it time to rethink quantum gravity?
• Observational constraints on varying fundamental constants in a minimal CPC model
• Primordial regular black holes as all the dark matter. III. Covariant canonical quantum gravity models
• Black Hole Evaporation in Loop Quantum Gravity
• Bulk area law for boundary entanglement in spin network states: entropy corrections and horizon-like regions from volume correlations
• Evolution Operator Can Always be Separated into the Product of Holonomy and Dynamic Operators
• Visions in Quantum Gravity
• 100 years of mathematical cosmology: Models, theories, and problems
• Non-abelian symmetry-resolved entanglement entropy
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• Implications of Tarski's Undefinability Theorem on the Theory of Everything
• An Effective Model for the Quantum Schwarzschild Black Hole: Weak Deflection Angle, Quasinormal Modes and Bounding of Greybody Factor
• Superradiant Axionic Black-Hole Clouds as Seeds for Graviton Squeezing
• Cosmological implications of generalized holonomy corrections
• Decoding quantum gravity information with black hole accretion disk
• Loop Quantum Gravity and Quantum Information
• Euclidean Dynamical Triangulations Revisited
• The Barbero-Immirzi Parameter: An Enigmatic Parameter of Loop Quantum Gravity
• Quantum cosmology of pure connection general relativity
• Replica Trick Calculation for Entanglement Entropy of Static Black Hole Spacetimes
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• Symmetric black-to-white hole solutions with a cosmological constant
• Universal properties of the evolution of the Universe in modified loop quantum cosmology
• Path integral and conformal instability in nonlocal quantum gravity
• The effective Equation of State in Palatini $f(R)$ cosmology
• Impact of generalized holonomy corrections on the cosmological primordial power spectra
• Admissible Causal Structures and Correlations
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• Intertwiner Entanglement Excitation and Holonomy Operator
• Fractional quantum mechanics meets quantum gravity phenomenology
• Hamiltonian Analysis of Pre-geometric Gravity
• Tidal Stretching and Compression in Black Bounce Backgrounds
• Squeezed gravitons from superradiant axion fields around rotating black holes
• Lectures in Quantum Gravity
• The Relation between Wavefunction and 3D Space Implies Many Worlds with Local Beables and Probabilities
• Black Hole Remnants from Dynamical Dimensional Reduction?
• Stochastic dynamics for Group Field Theories
• Cosmology in Lorentzian Regge calculus: causality violations, massless scalar field and discrete dynamics
• Gravitational lensing in holonomy corrected spherically symmetric black holes with phantom global monopoles
• Relational dynamics and Page-Wootters formalism in group field theory
• Probing cosmological singularities with quantum fields: Open and closed FLRW universes
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• Gravitational Collapse via Wheeler-DeWitt Equation
• From loop quantum gravity to cosmology: the two-vertex model
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• Precision predictions of Starobinsky inflation with self-consistent Weyl-squared corrections
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• 3D-Space and the preferred basis cannot uniquely emerge from the quantum structure
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• Overdamped quasibound states inside a Schwarzschild black hole
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• Modified Compton Effect and CMB Anisotropy
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