Results 11 to 20 of about 120,147 (251)
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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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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Noncommutative Quantum Cosmology [PDF]
General Relativity and Gravitation, 2004 We consider noncommutative quantum cosmology in the case of the low-energy string effective theory. Exacts solutions are found and compared with the commutative case.The Noncommutative quantum cosmology is considered in the case of the low-energy string ...
A. Connes +12 more
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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 the Euclidean version. In particular, we revisit the mini-superspace calculation of the Feynman path integral for quantum gravity with a positive cosmological constant. Instead of rotating to Euclidean time, we deform the contour of integration over metrics
Feldbrugge, Job +2 more
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Noncommutative Quantum Cosmology [PDF]
Physical Review Letters, 2002 We propose a model for noncommutative quantum cosmology by means of a deformation of minisuperspace. For the Kantowski-Sachs metric we are able to find the exact wave function. We construct wave packets and show that new quantum states that ``compete'' to be the most probable state appear, in clear contrast with the commutative case.
Garcia-Compean, H. +2 more
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Nonlinear quantum cosmology [PDF]
General Relativity and Gravitation, 2009 Final Journal version: Further clarification in Introduction and Conclusion. references added.
Nguyen, L.-H., Parwani, R.R.
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Quantum cosmological backreactions. II. Purely homogeneous quantum cosmology
Physical Review D, 2022 This is the second paper in a series of four in which we use space adiabatic methods in order to incorporate backreactions among the homogeneous and between the homogeneous and inhomogeneous degrees of freedom in quantum cosmological perturbation theory. The purpose of the present paper is twofold. On the one hand, it illustrates the formalism of space
J. Neuser, S. Schander, T. Thiemann
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Universe, 2021 The goal of this contribution is to present the properties of a class of quantum bouncing models in which the quantum bounce originates from the Dirac canonical quantization of a midi-superspace model composed of a homogeneous and isotropic background ...
Nelson Pinto-Neto
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Cosmological quantum billiards [PDF]
, 2012 The mini-superspace quantization of D=11 supergravity is equivalent to the quantization of a E10/K(E10) coset space sigma model, when the latter is restricted to the E10 Cartan subalgebra. As a consequence, the wavefunctions solving the relevant mini-superspace Wheeler-DeWitt equation involve automorphic (Maass wave) forms under the modular group W ...
Kleinschmidt, Axel, Nicolai, Hermann
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