Results 41 to 50 of about 2,562 (178)
DeWitt boundary condition is consistent in Hořava-Lifshitz quantum gravity
Physics Letters B, 2022 In quantum cosmology the DeWitt boundary condition is a proposal to set the wave function of the universe to vanish at the classical big-bang singularity.
Hiroki Matsui +2 more
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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
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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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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
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
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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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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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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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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
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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
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