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Related papers: Decoherence in the Dirac equation

200 papers

Each semigroup describing the time evolution of an open quantum system on a finite dimensional Hilbert space is related to a special structure of this space. It is shown how the space can be decomposed into subspaces: One is related to…

Mathematical Physics · Physics 2015-05-27 Bernhard Baumgartner , Heide Narnhofer

We examine the structure of the Clifford algebra associated with a Hermitian bilinear form and apply the result to a dynamical model of the relativistic point particle. The dynamics of the particle is described by a Dirac spinor with…

High Energy Physics - Theory · Physics 2007-05-23 Kaare Borchsenius

The Dirac monopole string is specified for de Sitter cosmological model. Dirac equation for spin 1/2 particle in presence of this monopole has been examined on the background of de Sitter space-time in static coordinates. Instead of spinor…

Quantum Physics · Physics 2011-09-15 V. M. Red'kov , E. M. Ovsiyuk , O. V. Veko

We prove the nonlinear local stability of Dirac masses for a kinetic model of alignment of particles on the unit sphere, each point of the unit sphere representing a direction. A population concentrated in a Dirac mass then corresponds to…

Analysis of PDEs · Mathematics 2014-09-25 Pierre Degond , Amic Frouvelle , Gaël Raoul

The destruction of quantum interference, decoherence, and the destruction of entanglement both appear to occur under the same circumstances. To address the connection between these two phenomena, we consider the evolution of arbitrary…

Quantum Physics · Physics 2009-11-10 P. J. Dodd , J. J. Halliwell

We establish soliton-like asymptotics for finite energy solutions to the Dirac equation coupled to a relativistic particle. Any solution with initial state close to the solitary manifold, converges in long time limit to a sum of traveling…

Mathematical Physics · Physics 2010-12-15 A. Komech , E. Kopylova , H. Spohn

These are introductory notes on the study of the Dirac equation in curved spacetime and its relation to hidden symmetries of the dynamics. We present general results on the relation between special spacetime tensors and hidden symmetries,…

General Relativity and Quantum Cosmology · Physics 2012-10-01 Marco Cariglia

Any positive-energy state of a free Dirac particle that is initially highly-localized, evolves in time by spreading at speeds close to the speed of light. This general phenomenon is explained by the fact that the Dirac evolution can be…

Quantum Physics · Physics 2015-06-26 A. J. Bracken , D. Ellinas , I. Smyrnakis

We study the Dirac oscillator for spin-1/2 particles in a spacetime containing a spinning cosmic string endowed with both curvature (disclination) and torsion (screw dislocation). The background geometry includes off-diagonal and is…

General Relativity and Quantum Cosmology · Physics 2025-09-29 Abdelmalek Boumali

Decoherence is the process via which quantum superpositions states are reduced to classical mixtures. Decoherence has been predicted for relativistically accelerated quantum systems, however examples to date have involved restricting the…

Quantum Physics · Physics 2019-01-16 Daiqin Su , Timothy C. Ralph

The decay of the overlap between a wave packet evolved with a Hamiltonian H and the same state evolved with H}+$\Sigma $ serves as a measure of the decoherence time $\tau_{\phi}$. Recent experimental and analytical evidence on classically…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 F. M. Cucchietti , H. M. Pastawski , R. Jalabert

The Dirac equation with both scalar and vector couplings describing the dynamics of a two-dimensional Dirac oscillator in the cosmic string spacetime is considered. We derive the Dirac-Pauli equation and solve it in the limit of the spin…

High Energy Physics - Theory · Physics 2019-07-18 Daniel F. Lima , Fabiano M. Andrade , Luis B. Castro , Cleverson Filgueiras , Edilberto O. Silva

In the Dirac theory for the motion of free relativistic electrons, highly oscillatory components appear in the time evolution of physical observables such as position, velocity, and spin angular momentum. This effect is known as…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 R. Winkler , U. Zülicke , Jens Bolte

Mapping the system evolution of a two-state system allows the determination of the effective system Hamiltonian directly. We show how this can be achieved even if the system is decohering appreciably over the observation time. A method to…

The emergence of classical behaviour in quantum theory is often ascribed to the interaction of a quantum system with its environment, which can be interpreted as environmental monitoring of the system. As a result, off-diagonal elements of…

Quantum Physics · Physics 2025-04-24 Dorje C. Brody , Eva-Maria Graefe , Rishindra Melanathuru

Compatibility of symmetric quantization of the Dirac equation in a curved space with general covariance gives a special representation of the spin connections in which their dot product with the Dirac gamma matrices becomes equal to the…

Quantum Physics · Physics 2017-10-03 A. D. Alhaidari

It is shown that, for spherically symmetric static backgrounds, a simple reduced Dirac equation can be obtained by using the Cartesian tetrad gauge in Cartesian holonomic coordinates. This equation is manifestly covariant under rotations so…

General Relativity and Quantum Cosmology · Physics 2010-11-19 Ion I. Cotăescu

The orthogonality of cat and displaced cat states, underlying Heisenberg limited measurement in quantum metrology, is studied in the limit of large number of states. The asymptotic expression for the corresponding state overlap function,…

Quantum Physics · Physics 2010-08-18 Raman Sharma , Prasanta K. Panigrahi

We deduce from a microscopic point of view the equation that describes how the state of a particle crossing a medium decoheres. We apply our results to the example of a particle crossing a gas, computing explicitly the Lindblad operators in…

Quantum Physics · Physics 2007-05-23 Alexandre Dominguez-Clarimon

We have recently argued that if one introduces a relational time in quantum mechanics and quantum gravity, the resulting quantum theory is such that pure states evolve into mixed states. The rate at which states decohere depends on the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Rodolfo Gambini , Rafael Porto , Jorge Pullin