Results 181 to 190 of about 113,880 (205)
Some of the next articles are maybe not open access.
Physical Review D, 1987
This paper considers the extension of the ideas of quantum cosmology and, in particular, the proposal of Hartle and Hawking for the boundary conditions of the Universe, to models which incorporate fermions in a realistic manner. We consider inhomogeneous fermionic perturbations about a homogeneous, isotropic minisuperspace background model, by ...
J. J. Halliwell, P. D. D’Eath
openaire +3 more sources
This paper considers the extension of the ideas of quantum cosmology and, in particular, the proposal of Hartle and Hawking for the boundary conditions of the Universe, to models which incorporate fermions in a realistic manner. We consider inhomogeneous fermionic perturbations about a homogeneous, isotropic minisuperspace background model, by ...
J. J. Halliwell, P. D. D’Eath
openaire +3 more sources
Annalen der Physik, 2001
AbstractDifferent models of quantum string minisuperspaces for both isotropic and anisotropic geometries are presented. As for the isotropic case the general model of axion‐dilaton cosmology of arbitrary curvature is studied and solved explicitly. In the anisotropic case Bianchi type I and IX and Kantowski‐Sachs geometries are investigated.
openaire +3 more sources
AbstractDifferent models of quantum string minisuperspaces for both isotropic and anisotropic geometries are presented. As for the isotropic case the general model of axion‐dilaton cosmology of arbitrary curvature is studied and solved explicitly. In the anisotropic case Bianchi type I and IX and Kantowski‐Sachs geometries are investigated.
openaire +3 more sources
Quantum cosmology with electromagnetism
Physical Review D, 1988We investigate the semiclassical quantum cosmology of the spatially homogeneous k = +1 Friedmann-Robertson-Walker minisuperspace model with the electromagnetic field included as a small perturbation on the gravitational background. The wave function is chosen adopting the Hartle-Hawking proposal. Owing to conformal invariance, the electromagnetic field
openaire +3 more sources
Decoherence in quantum cosmology
Physical Review D, 1989We discuss the manner in which the gravitational field becomes classical in quantum cosmology. This involves two steps. First, one must show that the quantum state of the gravitational field becomes strongly peaked about a set of classical configurations.
openaire +3 more sources
Physical Review, 1969
Summary: The Hamiltonian methods of Arnowitt, Deser, and Misner can be applied to homogeneous cosmological models, and prove to be an efficient way both of constructing the Einstein equations and of studying their solutions. By using an appropriate form for the metric, one finds that the constraint equations for these models can be solved explicitly ...
openaire +2 more sources
Summary: The Hamiltonian methods of Arnowitt, Deser, and Misner can be applied to homogeneous cosmological models, and prove to be an efficient way both of constructing the Einstein equations and of studying their solutions. By using an appropriate form for the metric, one finds that the constraint equations for these models can be solved explicitly ...
openaire +2 more sources
Quantum guidelines for solid-state spin defects
Nature Reviews Materials, 2021Gary Wolfowicz +2 more
exaly
The germanium quantum information route
Nature Reviews Materials, 2021Giordano Scappucci +2 more
exaly
Cosmology with the Laser Interferometer Space Antenna
Living Reviews in Relativity, 2023Germano Nardini
exaly
Materials challenges for trapped-ion quantum computers
Nature Reviews Materials, 2021Kenneth R Brown +2 more
exaly
Circuit quantum electrodynamics
Reviews of Modern Physics, 2021Alexandre Blais, Andreas J Wallraff
exaly