Results 31 to 40 of about 2,648,408 (181)
Effective f(R) Actions for Modified Loop Quantum Cosmologies via Order Reduction
Universe, 2023 General Relativity is an extremely successful theory, at least for weak gravitational fields; however, it breaks down at very high energies, such as in correspondence to the initial singularity.
Ana Rita Ribeiro +2 more
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Dark Energy Problem, Physics of Early Universe and Some New Approaches in Gravity
Entropy, 2012 The dark energy problem is studied based on the approach associated with the cosmological term in General Relativity that is considered as a dynamic quantity.
Alexander Shalyt-Margolin
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European Physical Journal C: Particles and Fields, 2022 We consider some background tests of standard cosmology in the context of Hořava gravity with different scaling dimensions for space and time, which has been proposed as a renormalizable, higher-derivative, Lorentz-violating quantum gravity model without
Nils A. Nilsson, Mu-In Park
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The Vacuum State of Primordial Fluctuations in Hybrid Loop Quantum Cosmology
Universe, 2018 We investigate the role played by the vacuum of the primordial fluctuations in hybrid Loop Quantum Cosmology. We consider scenarios where the inflaton potential is a mass term and the unperturbed quantum geometry is governed by the effective dynamics of ...
Beatriz Elizaga Navascués +2 more
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Non-metricity signatures on the Higgs boson signal strengths at the LHC
Journal of High Energy Physics, 2022 In this work we study the high-energy Higgs boson phenomenology associated to the non-metricity scale Λ Q at the LHC. Non-metricity is present in more generic non-Riemannian geometries describing gravity beyond General Relativity and exhibits nice ...
Victor Ilisie
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Generalized Rest Mass and Dirac’s Monopole in 5D Theory and Cosmology
Universe, 2021 It is shown that the 5D geodetic equations and 5D Ricci identities give us a way to create a new viewpoint on some problems of modern physics, astrophysics, and cosmology.
Boris G. Aliyev
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On the cosmological gravitational waves and cosmological distances [PDF]
Physics Letters B 778 (2018) 332, 2017 We show that solitonic cosmological gravitational waves propagated through the Friedmann universe and generated by the inhomogeneities of the gravitational field near the Big Bang can be responsible for increase of cosmological distances.
arxiv +1 more source
Effective actions for loop quantum cosmology in fourth-order gravity
European Physical Journal C: Particles and Fields, 2021 Loop quantum cosmology (LQC) is a theory which renders the Big Bang initial singularity into a quantum bounce, by means of short-range repulsive quantum effects at the Planck scale.
Marcello Miranda +3 more
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Group Field Theory and Its Cosmology in a Matter Reference Frame
Universe, 2018 While the equations of general relativity take the same form in any coordinate system, choosing a suitable set of coordinates is essential in any practical application.
Steffen Gielen
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Two-photon amplitude interferometry for precision astrometry
The Open Journal of Astrophysics, 2022 Improved quantum sensing of photons from astronomical objects could provide high resolution observations in the optical benefiting numerous fields, including general relativity, dark matter studies, and cosmology.
Paul Stankus +3 more
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