Symmetry Breaking in Quantum Phenomena

A special issue of Symmetry (ISSN 2073-8994). This special issue belongs to the section "Physics".

Deadline for manuscript submissions: closed (30 September 2018) | Viewed by 7233

Special Issue Editors


E-Mail Website1 Website2 Website3
Guest Editor
Department of Theoretical Physics, Atomic Physics and Optics, Institute of Mathematical Research (IMUVA), University of Valladolid, 47011 Valladolid, Spain
Interests: mathematical modelling of quantum phenomena; supersymmetric quantum mechanics; mathematical modelling of topological materials; supersymmetric and superintegrable dynamical systems; soliton and kink solutions of nonlinear partial differential equations; phase space quantum mechanics, Wigner functions and applications; symmetries of physical systems in spaces of constant curvature; position-dependent mass problems in quantum mechanics; symmetries of finite difference equations

E-Mail
Guest Editor
1. Departamento de Física Teórica, Atómica y Óptica and IMUVA, Universidad de Valladolid, Paseo Belén 7, 47011 Valladolid, Spain
2. Facultad de Educación de Palencia, Campus La Yutera, Universidad de Valladolid, Avd. Madrid, 44, 34004 Palencia, Spain
Interests: quantum field theory; vacuum phenomena; quantum optics; cosmic strings

Special Issue Information

Dear Colleagues,

The break of symmetries in physical systems, either in or out of equilibrium, gives rise to a number of phenomena, which allow to probe topological and symmetric properties of the states of the systems, as well as of their underlying field theory. In the case of discrete symmetries, for instance, the presence of a magnetic field breaks the time-reversal symmetry in free space, and the electromagnetic vacuum is said to present magnetic birefringence; likewise, time-reversal violation modifies the Casimir interaction between non-reciprocal media; in magneto-chiral media, it is the simultaneous violation of parity and time reversal that gives rise to a vacuum momentum; and the break of parity in an asymmetrically excited system is at the origin of the apparent violation of the action-reaction principle. In addition, spontaneous symmetry breaking in field theories which undergo either thermal or quantum phase transitions leads to the formation of topological defects such as cosmic strings, domain walls, monopoles, vortices, etc. By studying the properties of the resultant network of topological defects, valuable information about the parameters and the symmetry of the underlying field theory can be extracted.

It is the aim of this Special Issue to gather works on these topics, which provide a representative overview, as well as to stimulate progress in their investigation.

Prof. Luis Miguel Nieto
Dr. Manuel Donaire
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Symmetry is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Parity violation
  • Time reversal violation
  • Vacuum birefringence
  • Casimir momentum
  • Non-reciprocal media
  • Directional spontaneous emission
  • Spontaneous symmetry breaking
  • Topological defects formation: cosmic strings, domain walls, monopoles, vortices, disclination lines
  • Kibble-Zurek mechanism
  • Supersymmetry breaking
  • Beta decay

Published Papers (3 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

14 pages, 686 KiB  
Article
Field Fluctuations and Casimir Energy of 1D-Fermions
by Manuel Donaire, José María Muñoz-Castañeda, Luis Miguel Nieto and Marcos Tello-Fraile
Symmetry 2019, 11(5), 643; https://doi.org/10.3390/sym11050643 - 07 May 2019
Cited by 6 | Viewed by 2276
Abstract
We investigate the self-adjoint extensions of the Dirac operator of a massive one-dimensional field of mass m confined in a finite filament of length L. We compute the spectrum of vacuum fluctuations of the Dirac field under the most general dispersionless boundary [...] Read more.
We investigate the self-adjoint extensions of the Dirac operator of a massive one-dimensional field of mass m confined in a finite filament of length L. We compute the spectrum of vacuum fluctuations of the Dirac field under the most general dispersionless boundary conditions. We identify its edge states in the mass gap within a set of values of the boundary parameters, and compute the Casimir energy of the discrete normal modes. Two limit cases are considered, namely, that of light fermions with m L 1 , and that of heavy fermions for which m L 1 . It is found that both positive and negative energies are obtained for different sets of values of the boundary parameters. As a consequence of our calculation we demonstrate that the sign of the quantum vacuum energy is not fixed for exchange-symmetric plates (parity-invariant configurations), unlike for electromagnetic and scalar fields. Full article
(This article belongs to the Special Issue Symmetry Breaking in Quantum Phenomena)
Show Figures

Figure 1

15 pages, 1647 KiB  
Article
Exactly Solvable One-Qubit Driving Fields Generated via Nonlinear Equations
by Marco Enríquez and Sara Cruz y Cruz
Symmetry 2018, 10(11), 567; https://doi.org/10.3390/sym10110567 - 01 Nov 2018
Cited by 8 | Viewed by 2102
Abstract
Using the Hubbard representation for S U ( 2 ) , we write the time-evolution operator of a two-level system in the disentangled form. This allows us to map the corresponding dynamical law into a set of nonlinear coupled equations. In order to [...] Read more.
Using the Hubbard representation for S U ( 2 ) , we write the time-evolution operator of a two-level system in the disentangled form. This allows us to map the corresponding dynamical law into a set of nonlinear coupled equations. In order to find exact solutions, we use an inverse approach and find families of time-dependent Hamiltonians whose off-diagonal elements are connected with the Ermakov equation. A physical model with the so-obtained Hamiltonians is discussed in the context of the nuclear magnetic resonance phenomenon. Full article
(This article belongs to the Special Issue Symmetry Breaking in Quantum Phenomena)
Show Figures

Figure 1

23 pages, 1191 KiB  
Article
Transition from the Wave Equation to Either the Heat or the Transport Equations through Fractional Differential Expressions
by Fernando Olivar-Romero and Oscar Rosas-Ortiz
Symmetry 2018, 10(10), 524; https://doi.org/10.3390/sym10100524 - 19 Oct 2018
Cited by 8 | Viewed by 2483
Abstract
We present a model that intermediates among the wave, heat, and transport equations. The approach considers the propagation of initial disturbances in a one-dimensional medium that can vibrate. The medium is nonlinear in such a form that nonlocal differential expressions are required to [...] Read more.
We present a model that intermediates among the wave, heat, and transport equations. The approach considers the propagation of initial disturbances in a one-dimensional medium that can vibrate. The medium is nonlinear in such a form that nonlocal differential expressions are required to describe the time evolution of solutions. Nonlocality was modeled with a space-time fractional differential equation of order 1 α 2 in time, and order 1 β 2 in space. We adopted the notion of Caputo for the time derivative and the Riesz pseudo-differential operator for the space derivative. The corresponding Cauchy problem was solved for zero initial velocity and initial disturbance, represented by either the Dirac delta or the Gaussian distributions. Well-known results for the conventional partial differential equations of wave propagation, diffusion, and (modified) transport processes were recovered as particular cases. In addition, regular solutions were found for the partial differential equation that arises from α = 2 and β = 1 . Unlike the above conventional cases, the latter equation permits the presence of nodes in its solutions. Full article
(This article belongs to the Special Issue Symmetry Breaking in Quantum Phenomena)
Show Figures

Figure 1

Back to TopTop