Results 11 to 20 of about 115,765 (198)
Universe, 2023 Quantum cosmology aims to develop a quantum theory of the universe, attempting to answer open questions of physical cosmology, mainly related to the early epochs of the universe. Such a theory aims to unite relativity theory and quantum theory. Here, the
Shreya Banerjee
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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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Cosmic Tangle: Loop Quantum Cosmology and CMB Anomalies
Universe, 2021 Loop quantum cosmology is a conflicted field in which exuberant claims of observability coexist with serious objections against the conceptual and physical viability of its current formulations.
Martin Bojowald
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Frontiers in Astronomy and Space Sciences, 2021 In this review, we investigate the question of backreaction in different approaches to cosmological perturbation theory, and with a special focus on quantum theoretical aspects. By backreaction we refer here to the effects of matter field or cosmological
S. Schander, S. Schander, T. Thiemann
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Is a loopy and noncommutative early Universe viable?
Physics Letters B, 2023 We conduct a (pre-)inflationary dynamics study of the chaotic quadratic potential within the framework of a simple noncommutative extension of effective loop quantum cosmology put forward recently.
Luis Rey Díaz-Barrón +3 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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Testing loop quantum cosmology [PDF]
, 2017 Loop quantum cosmology predicts that quantum gravity effects resolve the big-bang singularity and replace it by a cosmic bounce. Furthermore, loop quantum cosmology can also modify the form of primordial cosmological perturbations, for example by ...
Wilson-Ewing, Edward
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