Results 51 to 60 of about 39,130 (174)
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
openaire +3 more sources
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
core +1 more source
Frontiers in Astronomy and Space Sciences, 2021 While the standard, six-parameter, spatially flat ΛCDM model has been highly successful, certain anomalies in the cosmic microwave background bring out a tension between this model and observations.
Abhay Ashtekar +3 more
doaj +1 more source
Observational Constraints on Loop Quantum Cosmology
Physical Review Letters, 2011 In the inflationary scenario of loop quantum cosmology in the presence of inverse-volume corrections, we give analytic formulas for the power spectra of scalar and tensor perturbations convenient to compare with observations. Since inverse-volume corrections can provide strong contributions to the running spectral indices, inclusion of terms higher ...
Bojowald, M. +2 more
openaire +5 more sources
Tachyonic inflation in loop quantum cosmology
European Physical Journal C: Particles and Fields, 2019 A tachyon field might be responsible for cosmological inflation at an early time and contribute to cosmological dark matter at a later time. We investigate tachyonic inflation by analyzing a tachyon field with different potentials in the framework of ...
Kui Xiao
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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.
openaire +3 more sources
Non-Gaussianity in loop quantum cosmology [PDF]
Physical Review D, 2018 Minor updates: current version matches the accepted PRD ...
Agullo, Ivan +2 more
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Universal features of quantum bounce in loop quantum cosmology
Physics Letters B, 2017 In this Letter, we study analytically the evolutions of the flat Friedmann–Lemaitre–Robertson–Walker (FLRW) universe and its linear perturbations in the framework of the dressed metric approach in loop quantum cosmology (LQC). Assuming that the evolution
Tao Zhu +4 more
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Thermodynamics in new model of loop quantum cosmology
European Physical Journal C: Particles and Fields, 2021 The thermodynamic properties of loop quantum cosmology (LQC) without considering the Lorentz term were established in Li and Zhu (Adv High Energy Phys 2009:905705, 2009).
Xiangdong Zhang
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