Results 41 to 50 of about 2,756,107 (244)
Journal of High Energy Physics, 2020 It was recently shown that the homogeneous and isotropic cosmology of a massless scalar field coupled to general relativity exhibits a new hidden conformal invariance under Mobius transformation of the proper time, additionally to the invariance under ...
Jibril Ben Achour, Etera R. Livine
doaj +1 more source
Cosmology models with Ω_M-dependent cosmological constant [PDF]
Gen.Rel.Grav. 35 (2003) 1007-1016, 2002 We investigate the evolution of the scale factor in a cosmological model in which the cosmological constant is given by the scalar arisen by the contraction of the stress-energy tensor.
arxiv +1 more source
Editorial: Loop Quantum Cosmology
Frontiers in Astronomy and Space Sciences, 2022 Loop Quantum Cosmology is the application to cosmology of the nonperturbative canonical quantization program of General Relativity provided by Loop Quantum Gravity. This has been an active field of investigation for more than 20 years.
Beatriz Elizaga Navascués +2 more
semanticscholar +1 more source
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
Braneworlds and Quantum States of Relativistic Shells [PDF]
, 2007 We review some applications of relativistic shells that are relevant in the context of quantum gravity/quantum cosmology. Using a recently developed approach, the stationary states of this general relativistic system can be determined in the ...
Ansoldi, Stefano
core +2 more sources
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
Combining general relativity and quantum theory: points of conflict and contact [PDF]
, 2001 Issues related to bringing together the principles of general relativity and quantum theory are discussed. After briefly summarizing the points of conflict between the two formalisms I focus on four specific themes in which some contact has been ...
T. Padmanabhan
semanticscholar +1 more source
Black Hole Thermodynamics [PDF]
, 2014 The discovery in the early 1970s that black holes radiate as black bodies has radically affected our understanding of general relativity, and offered us some early hints about the nature of quantum gravity.
Carlip, S.
core +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