Results 51 to 60 of about 77,468 (282)
Observational consequences of Bianchi I spacetimes in loop quantum cosmology [PDF]
Physical Review D, 2020 Anisotropies generically dominate the earliest stages of expansion of a homogeneous universe. They are particularly relevant in bouncing models, since shears grow in the contracting phase of the cosmos, making the isotropic situation unstable. This paper
I. Agulló, J. Olmedo, V. Sreenath
semanticscholar +1 more source
Noncovariance of the dressed-metric approach in loop quantum cosmology [PDF]
Physical Review D, 2020 The dressed-metric approach is shown to violate general covariance by demonstrating that it cannot have an off-shell completion in which the correct infinitesimal relations of space-time hypersurface deformations are realized. The main underlying reason--
M. Bojowald
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The time-dependent mass of cosmological perturbations in loop quantum cosmology: Dapor–Liegener regularization [PDF]
Classical and quantum gravity, 2020 In this work, we compute the time-dependent masses that govern the dynamics of scalar and tensor perturbations propagating on an effective flat, homogeneous, and isotropic background within the framework of loop quantum cosmology (LQC), regularized ...
Alejandro Garc'ia-Quismondo +2 more
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The mass of cosmological perturbations in Loop Quantum Cosmology
The Fifteenth Marcel Grossmann Meeting, 2022 Sixth Tux workshop on Quantum Gravity. Monday, February 19 to Friday, February 23. Tux, Austria (2018). ..-https://www.gravity.physik.fau.de/events/tux6/
Mena Marugán, Guillermo A. +2 more
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Loop quantum cosmology and spin foams [PDF]
Physics Letters B, 2009 Loop quantum cosmology (LQC) is used to provide concrete evidence in support of the general paradigm underlying spin foam models (SFMs). Specifically, it is shown that: i) the physical inner product in the timeless framework equals the transition amplitude in the deparameterized theory; ii) this quantity admits a %convergent vertex expansion a la SFMs ...
Abhay Ashtekar +2 more
openalex +3 more sources
Polymer Dynamics of Isotropic Universe in Ashtekar and in Volume Variables
Universe, 2022 We analyze the semiclassical and quantum polymer dynamics of the isotropic Universe in terms of both the standard Ashtekar-Barbero-Immirzi connection and its conjugate momentum and also of the new generalized coordinate conjugate to the Universe volume ...
Eleonora Giovannetti +3 more
doaj +1 more source
Gravitational particle production in loop quantum cosmology [PDF]
Physical Review D, 2020 We investigate the gravitational particle production in the bounce phase of Loop Quantum Cosmology (LQC). We perform both analytical and numerical analysis of the particle production process in a LQC scenario with Bunch-Davies vacuum initial condition in
L. Graef, R. O. Ramos, G. S. Vicente
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Does the Loop Quantum μo Scheme Permit Black Hole Formation?
Universe, 2021 We explore the way different loop quantization prescriptions affect the formation of trapped surfaces in the gravitational collapse of a homogeneous dust cloud, with particular emphasis on the so-called μo scheme in which loop quantum cosmology was ...
Bao-Fei Li, Parampreet Singh
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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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Analytic and numerical study of scalar perturbations in loop quantum cosmology [PDF]
Physical Review DThe possibility that quantum geometry effects may alleviate the apparent tensions existing at large angular scales in the observations of the Cosmic Microwave Background explains the increasing interest in considering primordial perturbations within the ...
G. A. Mena Marugán +2 more
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