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Loop quantum cosmology and singularities [PDF]
Scientific Reports, 2017 Loop quantum gravity is believed to eliminate singularities such as the big bang and big crunch singularity. This belief is based on studies of so-called loop quantum cosmology which concerns symmetry-reduced models of quantum gravity. In this paper, the
Ward Struyve
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Living Reviews in Relativity, 2008 Quantum gravity is expected to be necessary in order to understand situations in which classical general relativity breaks down. In particular in cosmology one has to deal with initial singularities, i.e., the fact that the backward evolution of a ...
Bojowald Martin
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Hybrid Loop Quantum Cosmology: An Overview [PDF]
Frontiers in Astronomy and Space Sciences, 2021 Loop Quantum Gravity is a nonperturbative and background independent program for the quantization of General Relativity. Its underlying formalism has been applied successfully to the study of cosmological spacetimes, both to test the principles and ...
Beatriz Elizaga Navascués +1 more
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Annals of the New York Academy of Sciences, 1993 An elementary review of quantum cosmology.
Aryal +26 more
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Quantum String Cosmology [PDF]
Universe, 2021 We present a short review of possible applications of the Wheeler-De Witt equation to cosmological models based on the low-energy string effective action, and characterised by an initial regime of asymptotically flat, low energy, weak coupling evolution.
Maurizio Gasperini
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Time in Quantum Cosmology [PDF]
Universe, 2022 Time in quantum gravity is not a well-defined notion despite its central role in the very definition of dynamics. Using the formalism of quantum geometrodynamics, we briefly review the problem and illustrate it with two proposed solutions.
Claus Kiefer, Patrick Peter
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Lorentzian quantum cosmology [PDF]
Physical Review D, 2017 We argue that the Lorentzian path integral is a better starting point for quantum cosmology than its Euclidean counterpart. In particular, we revisit the minisuperspace calculation of the Feynman path integral for quantum gravity with a positive ...
Job Leon Feldbrugge +2 more
semanticscholar +7 more sources
Sum-over-histories origin of the composition laws of relativistic quantum mechanics and quantum cosmology [PDF]
, 1993 The scope of the paper has been broadened to include a more complete discussion of the following topics: The derivation of composition laws in quantum cosmology. The connection between the existence of a composition law in the sum over histories approach
J. J. Halliwell, Miguel Ortiz
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, 2022 Invited contribution to the Encyclopedia of Mathematical Physics (2nd edition), providing an overview over some main ideas and results in quantum cosmology. Key points: Canonical quantisation of homogeneous, isotropic cosmology; discussion of ambiguities in this quantisation; Construction of explicit solutions, attempts at physical interpretation ...
Steffen Gielen
semanticscholar +3 more sources
Zeitschrift für Naturforschung A, 2008 We give an introduction into quantum cosmology with emphasis on its conceptual parts. After a general motivation we review the formalism of canonical quantum gravity on which discussions of quantum cosmology are usually based.
Kiefer, Claus, Sandhoefer, Barbara
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