Results 61 to 70 of about 52,296 (249)
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
doaj +1 more source
Loop quantum cosmology of k=1 FRW models [PDF]
, 2006 The closed, k=1, FRW cosmology coupled to a massless scalar field is investigated in the framework of loop quantum cosmology using analytical and numerical methods.
Ashtekar, A +3 more
core +3 more sources
Little rip in classical and quantum f(R) cosmology [PDF]
, 2021 The little rip is a cosmological abrupt event predicted by some phantom dark energy models that could describe the future evolution of our Universe. This event can be interpreted as a big rip singularity delayed indefinitely, although in those models ...
Teodor Borislavov Vasilev +2 more
semanticscholar +1 more source
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
doaj +1 more source
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
doaj +1 more source
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
doaj +1 more source
Complex Riemannian Spacetime and Singularity-Free Black Holes and Cosmology
AxiomsAn approach is presented to address singularities in general relativity using a complex Riemannian spacetime extension. We demonstrate how this method can be applied to both black hole and cosmological singularities, specifically focusing on the ...
John W. Moffat
doaj +1 more source
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
doaj +1 more source
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
doaj +1 more source
, 1995 The Ashtekar variables have been use to find a number of exact solutions in quantum gravity and quantum cosmology. We investigate the origin of these solutions in the context of a number of canonical transformations (both complex and real) of the basic ...
A. Ashtekar +18 more
core +1 more source