English
Related papers

Related papers: A note on Quantum Fields in Conformally flat Space…

200 papers

A recently introduced numerical approach to quantum systems is analyzed. The basis of a Fock space is restricted and represented in an algebraic program. Convergence with increasing size of basis is proved and the difference between…

High Energy Physics - Theory · Physics 2007-05-23 Maciej Trzetrzelewski

This talk discusses the relation between spacetime-dependent scalars, such as couplings or fields, and the violation of Lorentz symmetry. A specific cosmological supergravity model demonstrates how scalar fields can acquire time-dependent…

General Relativity and Quantum Cosmology · Physics 2016-11-03 Ralf Lehnert

Quantum simulation provides quantum systems under study with analogous controllable quantum systems and has wide applications from condensed-matter physics to high energy physics and to cosmology. The quantum system of a homogeneous and…

General Relativity and Quantum Cosmology · Physics 2020-01-08 Sang Pyo Kim

We apply the supersymmetry approach to one-dimensional quantum systems with spatially-dependent mass, by including their ordering ambiguities dependence. In this way we extend the results recently reported in the literature. Furthermore, we…

High Energy Physics - Theory · Physics 2009-11-10 A. de Souza Dutra , Marcelo Hott , C. A. S. Almeida

Without a complete theory of quantum gravity, the question of how quantum fields and quantum particles behave in a superposition of spacetimes seems beyond the reach of theoretical and experimental investigations. Here we use an extension…

We study the most general cosmological model with real scalar field which is minimally coupled to gravity. Our calculations are based on Friedmann-Lemaitre-Robertson-Walker (FLRW) background metric. Field equations consist of three…

General Relativity and Quantum Cosmology · Physics 2023-03-22 Medine Ildes , Metin Arik

We study the spatial correlations of quantum fluctuations that can be observed in multi-mode spontaneous parametric down-conversion in the regime of high gain. A stochastic model has been solved numerically to obtain quantitative results…

Quantum Physics · Physics 2009-11-10 E. Brambilla , A. Gatti , M. Bache , L. A. Lugiato

The quantization of the Friedmann-Robertson-Walker spacetime in the presence of a negative cosmological constant was used in a recent paper to conclude that there are solutions that avoid singularities (big bang--big crunch) at the quantum…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Paolo Amore , Alfredo Aranda , Mayra Cervantes , J. L. Díaz-Cruz , Francisco M. Fernández

In this paper we analyze the relativistic quantum motion of charged spin-0 and spin-1/2 particles in the presence of a uniform magnetic field and scalar potentials in the cosmic string spacetime. In order to develop this analysis, we assume…

High Energy Physics - Theory · Physics 2021-04-12 E. R. Figueiredo Medeiros , E. R. Bezerra de Mello

We study space-time symmetries in scalar quantum field theory (including interacting theories) on static space-times. We first consider Euclidean quantum field theory on a static Riemannian manifold, and show that the isometry group is…

High Energy Physics - Theory · Physics 2007-05-23 Arthur Jaffe , Gordon Ritter

We give a numerical analysis of long-wavelength modes in the WKB approximation of cosmological scalar fields coupled to gravity via $\xi\phi^{2}R$. Massless fields are coupled conformally at $\xi=1/6$. Conformality can be preserved for…

High Energy Physics - Phenomenology · Physics 2009-11-11 Marcin Jankiewicz , Thomas W. Kephart

We show that in general a spacetime having a quantum group symmetry has also a scale dependent fractal dimension which deviates from its classical value at short scales, a phenomenon that resembles what observed in some approaches to…

High Energy Physics - Theory · Physics 2009-04-08 Dario Benedetti

We describe a quantum limit to measurement of classical spacetimes. Specifically, we formulate a quantum Cramer-Rao lower bound for estimating the single parameter in any one-parameter family of spacetime metrics. We employ the locally…

Quantum Physics · Physics 2017-11-15 T. G. Downes , J. R. van Meter , E. Knill , G. J. Milburn , C. M. Caves

A scalar field theory is constructed on an energy-momentum background of constant curvature. The generalization of the usual Feynamn rules for the flat geometry follows from the requirement of their covariance. The main result is that the…

General Physics · Physics 2023-03-22 Boris Ivetic

A physical interpretation of axioms of the differential structure of space-time is presented. Consequences of such interpretation for cosmic string's space-time with a scalar field are studied. It is shown that the assumption of smoothness…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Jacek Gruszczak

The Fock quantization of free fields propagating in cosmological backgrounds is in general not unambiguously defined due to the non-stationarity of the spacetime. For the case of a scalar field in cosmological scenarios it is known that the…

Mathematical Physics · Physics 2018-03-23 Jerónimo Cortez , Ilda Inácio Rodrigues , Mercedes Martín-Benito , José Velhinho

We study an analytical solution to the Einstein's equations in 2+1-dimensions. The space-time is dynamical and has a line symmetry. The matter content is a minimally coupled, massless, scalar field. Depending on the value of certain…

General Relativity and Quantum Cosmology · Physics 2015-06-25 G. Oliveira-Neto

The "conformal mass prescriptions" were used recently to calculate the mass of spacetimes in higher dimensional and higher curvature theories of gravity. These definitions are closely related to Komar integrals for spacetimes that are…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Nathalie Deruelle , Joseph Katz

The observed large-scale structure in our Universe is seen as a result of quantum fluctuations amplified by spacetime evolution. This, and related problems in cosmology, asks for an understanding of the quantum fields of the standard model…

We use Dirac's method for the quantization of constrained systems in order to quantize a spatially flat Friedmann-Lema\^{i}tre-Robertson-Walker spacetime in the context of $f(Q)$ cosmology. When the coincident gauge is considered, the…

General Relativity and Quantum Cosmology · Physics 2021-10-22 N. Dimakis , A. Paliathanasis , T. Christodoulakis
‹ Prev 1 4 5 6 7 8 10 Next ›