Results 81 to 90 of about 77,468 (282)
Absence of a Singularity in Loop Quantum Cosmology [PDF]
Physical Review Letters, 2001 It is shown that the cosmological singularity in isotropic minisuperspaces is naturally removed by quantum geometry. Already at the kinematical level, this is indicated by the fact that the inverse scale factor is represented by a bounded operator even though the classical quantity diverges at the initial singularity.
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Quantum reduced loop gravity and the foundation of loop quantum cosmology [PDF]
International Journal of Modern Physics D, 2016 Quantum reduced loop gravity is a promising framework for linking loop quantum gravity and the effective semiclassical dynamics of loop quantum cosmology. We review its basic achievements and its main perspectives, outlining how it provides a quantum description of the Universe in terms of a cuboidal graph which constitutes the proper framework for ...
Emanuele Alesci, Francesco Cianfrani
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Phenomenological implications of an alternative Hamiltonian constraint for quantum cosmology
, 2005 In this paper we review a model based on loop quantum cosmology that arises from a symmetry reduction of the self dual Plebanski action. In this formulation the symmetry reduction leads to a very simple Hamiltonian constraint that can be quantized ...
A. Ashtekar +6 more
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Background Dynamics of Pre-inflationary Scenario in Brans-Dicke Loop Quantum Cosmology [PDF]
Communications in Theoretical Physics, 2019 Recently the background independent nonperturbative quantization has been extended to various theories of gravity and the corresponding quantum effective cosmology has been derived, which provides us with necessary avenue to explore the pre-inflationary ...
Manabendra Sharma +2 more
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New loop quantum cosmology modifications from gauge-covariant fluxes [PDF]
Physical Review D, 2019 Loop quantum cosmology is a symmetry reduced quantization of cosmological spacetimes based on loop quantum gravity. While it has been successful in resolution of various cosmological singularities and connecting Planck scale physics to phenomenology, its
K. Liegener, Parampreet Singh
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Observational Exclusion of a Consistent Quantum Cosmology Scenario
, 2015 It is often argued that inflation erases all the information about what took place before it started. Quantum gravity, relevant in the Planck era, seems therefore mostly impossible to probe with cosmological observations.
Barrau, Aurelien +3 more
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Nonlinear (loop) quantum cosmology
Physical Review D, 2012 Inhomogeneous quantum cosmology is modeled as a dynamical system of discrete patches, whose interacting many-body equations can be mapped to a non-linear minisuperspace equation by methods analogous to Bose-Einstein condensation. Complicated gravitational dynamics can therefore be described by more-manageable equations for finitely many degrees of ...
Bojowald, Martin +4 more
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Symmetry Reduction of Loop Quantum Gravity
, 2011 The relation between standard Loop Quantum Cosmology and full Loop Quantum Gravity fails already at the first nontrivial step: The configuration space of Loop Quantum Cosmology can not be embedded into the configuration space of full Loop Quantum Gravity
Brunnemann, Johannes, Koslowski, Tim A.
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Inhomogeneous Loop Quantum Cosmology: Hybrid Quantization of the Gowdy Model [PDF]
, 2010 The Gowdy cosmologies provide a suitable arena to further develop Loop Quantum Cosmology, allowing the presence of inhomogeneities. For the particular case of Gowdy spacetimes with the spatial topology of a three-torus and a content of linearly polarized
A. Ashtekar +6 more
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Quantum cosmology of (loop) quantum gravity condensates: an example [PDF]
, 2014 Spatially homogeneous universes can be described in (loop) quantum gravity as condensates of elementary excitations of space. Their treatment is easiest in the second-quantized group field theory formalism, which allows the adaptation of techniques from ...
Steffen Gielen
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