Results 101 to 110 of about 75,052 (218)
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
Singular Electromagnetics: From Phase Singularities to Optical Skyrmions and Beyond
Advanced Physics Research, Volume 4, Issue 5, May 2025.Singular electromagnetics/optics studies multidimensional topological defects of electromagnetic fields (also known as optical singularities), including phase and polarization singularities, 3D singularities (e.g., optical skyrmions, merons, hopfions, knots, links, and Möbius strips), and even higher‐dimensional singularities.
Jie Yang +3 more
wiley +1 more source
Loop Quantum Cosmology: A cosmological theory with a view [PDF]
Journal of Physics: Conference Series, 2011 Loop Quantum Gravity is a background independent, nonperturbative approach to the quantization of General Relativity. Its application to models of interest in cosmology and astrophysics, known as Loop Quantum Cosmology, has led to new and exciting views of the gravitational phenomena that took place in the early universe, or that occur in spacetime ...
openaire +4 more sources
Quantum Gravitational Non-Singular Tunneling Wavefunction Proposal
Physical Sciences Forum, 2023 It has recently been shown that the tunneling wavefunction proposal is consistent with loop quantum geometry corrections, including both holonomy and inverse scale factor corrections, in the gravitational part of a spatially closed isotropic model with a
Meysam Motaharfar, Parampreet Singh
doaj +1 more source
Dark Dimension With (Little) Strings Attached
Fortschritte der Physik, Volume 73, Issue 4, April 2025.Abstract A relation between dark energy and the scale of new physics in weakly coupled string theory is motivated. This mixing between infrared and ultraviolet physics leads to a unique corner for real‐world phenomenology: barring fine‐tunings, the authors are naturally led to the “dark dimension” scenario, a single mesoscopic extra dimension of micron
Ivano Basile, Dieter Lüst
wiley +1 more source
Inflation and Loop Quantum Cosmology [PDF]
Proceedings of 35th International Conference of High Energy Physics — PoS(ICHEP 2010), 2011 5 pages, Proceedings of the 35th International Conference on High Energy Physics, Paris, 2010 (ICHEP 2010)
openaire +3 more sources
Positive cosmological constant in loop quantum cosmology [PDF]
Physical Review D, 2012 The k=0 Friedmann Lemaitre Robertson Walker model with a positive cosmological constant and a massless scalar field is analyzed in detail. If one uses the scalar field as relational time, new features arise already in the Hamiltonian framework of classical general relativity: In a finite interval of relational time, the universe expands out to infinite
Abhay Ashtekar +3 more
openaire +3 more sources
Living Reviews in Relativity, 2008 Quantum gravity is expected to be necessary in order to understand situations in which classical general relativity breaks down. In particular in cosmology one has to deal with initial singularities, i.e., the fact that the backward evolution of a ...
Bojowald Martin
doaj
Probability of warm inflation in loop quantum cosmology [PDF]
Physical Review D, 2018 Warm inflation is analyzed in the context of Loop Quantum Cosmology (LQC). The bounce in LQC provides a mean through which a Liouville measure can be defined, which has been used previously to characterize the a priori probability for inflation in LQC ...
L. Graef, R. O. Ramos
semanticscholar +1 more source
Foundations of Ghost Stability
Fortschritte der Physik, Volume 73, Issue 4, April 2025.Abstract The authors present a new method to analytically prove global stability in ghost‐ridden dynamical systems. The proposal encompasses all prior results and consequentially extends them. In particular, it is shown that stability can follow from a conserved quantity that is unbounded from below, contrary to expectation.
Verónica Errasti Díez +2 more
wiley +1 more source