Results 11 to 20 of about 113,880 (205)
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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Supersymmetry and quantum cosmology [PDF]
Physics Letters B, 2001 19 ...
F. Assaoui, T. Lhallabi
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Modular quantum cosmology [PDF]
Classical and Quantum Gravity, 1999 Latex, 23 pages, 1 figure.
Ricardo Schiappa, Orfeu Bertolami
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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.
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Classical and Quantum Solutions and the Problem of Time in $R^2$ Cosmology [PDF]
, 1995 We have studied various classical solutions in $R^2$ cosmology. Especially we have obtained general classical solutions in pure $R^2$\ cosmology. Even in the quantum theory, we can solve the Wheeler-DeWitt equation in pure $R^2$\ cosmology exactly ...
Banks T +22 more
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The Semiclassical Limit of Loop Quantum Cosmology [PDF]
, 2001 The continuum and semiclassical limits of isotropic, spatially flat loop quantum cosmology are discussed, with an emphasis on the role played by the Barbero-Immirzi parameter \gamma in controlling space-time discreteness.
Ashtekar A +20 more
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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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The Quantum Cosmological Constant [PDF]
Symmetry, 2019 We present an extension of general relativity in which the cosmological constant becomes dynamical and turns out to be conjugate to the Chern–Simons invariant of the Ashtekar connection on a spatial slicing. The latter has been proposed Soo and Smolin as a time variable for quantum gravity: the Chern–Simons time.
Alexander, S, Magueijo, J, Smolin, L
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The Curious Concept That Almost Nobody Seemed to Care About at First: Virtual Particles in the Post-War Period. [PDF]
Ber WissAbstract Short‐lived, unobservable, and not subject to the usual rules of conservation of energy and momentum, virtual particles—an integral part of the conceptual framework of quantum field theory (QFT)—exhibit a number of curious characteristics which, in recent decades, have in part fueled important discussions about their ontological status ...
Martinez JP.
europepmc +2 more sources
Higher dimensional Loop Quantum Cosmology [PDF]
, 2015 Loop quantum cosmology(LQC) is the symmetric model of loop quantum gravity. In this paper, we generalize the structure of loop quantum cosmology to the theories with arbitrary spacetime dimensions.
Zhang, Xiangdong
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