Quantum cosmology: a review

Abstract

In quantum cosmology, one applies quantum physics to the whole universe. While no unique version and no completely well-defined theory is available yet, the framework gives rise to interesting conceptual, mathematical and physical questions. This review presents quantum cosmology in a new picture that tries to incorporate the importance of inhomogeneity: De-emphasizing the traditional minisuperspace view, the dynamics is rather formulated in terms of the interplay of many interacting "microscopic" degrees of freedom that describe the space-time geometry. There is thus a close relationship with more-established systems in condensed-matter and particle physics even while the large set of space-time symmetries (general covariance) requires some adaptations and new developments. These extensions of standard methods are needed both at the fundamental level and at the stage of evaluating the theory by effective descriptions.

45 pages, invited review

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Cited by in corpus (77)

• Hořava Gravity at a Lifshitz Point: A Progress Report
• Quantum Cosmology from Group Field Theory Condensates: a Review
• Pre-inflationary universe in loop quantum cosmology
• The universe as a quantum gravity condensate
• Quantum Cosmology of $f(R,T)$ gravity
• Beyond Einstein's General Relativity: Hybrid metric-Palatini gravity and curvature-matter couplings
• Emergence of a low spin phase in group field theory condensates
• Bouncing compact objects I: Quantum extension of the Oppenheimer-Snyder collapse
• Covariance in models of loop quantum gravity: Gowdy systems
• Conditional symmetries in axisymmetric quantum cosmologies with scalar fields and the fate of the classical singularities
• String Tension between de Sitter vacua and Curvature Corrections
• Loops rescue the no-boundary proposal
• 3+1 Formulation of the Standard-Model Extension Gravity Sector
• The Einstein dark energy model
• Protected $SL(2,\mathbb{R})$ Symmetry in Quantum Cosmology
• Non-adiabatic Evolution of Primordial Perturbations and non-Gaussinity in Hybrid Approach of Loop Quantum Cosmology
• Phenomenological implications of modified loop cosmologies: an overview
• Scalar and tensor perturbations in loop quantum cosmology: High-order corrections
• Time in quantum cosmology
• Polymer Quantum Cosmology: Lifting quantization ambiguities using a $SL(2,\mathbb{R})$ conformal symmetry
• Cosmological ${\alpha }^{\prime }$-corrections from the functional renormalization group
• Quantum dynamics of the black hole interior in LQC
• Towards the map of quantum gravity
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• Phenomenology of Quantum Reduced Loop Gravity in the isotropic cosmological sector
• Minisuperspace Quantum Cosmology in Metric and Affine Theories of Gravity
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• The Cosmological Spinor
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