Some conceptual issues in loop quantum cosmology

Abstract

Loop quantum gravity is a mature theory. To proceed to explicit calculations in cosmology, it is necessary to make assumptions and simplifications based on the symmetries of the cosmological setting. Symmetry reduction is especially critical when dealing with cosmological perturbations. The present article reviews several approaches to the problem of building a consistent formalism that describes the dynamics of perturbations on a quantum spacetime and tries to address their respective strengths and weaknesses. We also review the main open issues in loop quantum cosmology.

Invited article for an IJMP volume dedicated to loop quantum gravity

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Cited by in corpus (17)

• Hořava Gravity at a Lifshitz Point: A Progress Report
• Pre-inflationary universe in loop quantum cosmology
• Critical evaluation of common claims in loop quantum cosmology
• Preinflationary dynamics in loop quantum cosmology: Monodromy Potential
• Primordial power spectrum from the Dapor-Liegener model of loop quantum cosmology
• Pre-inflationary dynamics in loop quantum cosmology: Power-law potentials
• Non-Gaussianity in Loop Quantum Cosmology
• Primordial non-Gaussianity and power asymmetry with quantum gravitational effects in loop quantum cosmology
• Preinflationary dynamics of $\alpha -$attractor in loop quantum cosmology
• Some Clarifications on the Duration of Inflation in Loop Quantum Cosmology
• Scalar spectra of primordial perturbations in loop quantum cosmology
• Quantum fields in the background spacetime of a loop quantum gravity black hole
• Warm bounce in loop quantum cosmology and the prediction for the duration of inflation
• Revisiting pre-inflationary universe of family of $\alpha -$attractor in loop quantum cosmology
• Preinflationary dynamics of power-law potential in loop quantum cosmology
• Gravitational Particle Production and the Validity of Effective Descriptions in Loop Quantum Cosmology
• Loop Quantum Cosmology with a noncommutative quantum deformed photon gas