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We show that the dynamical group of an electron in a constant magnetic field is the group of symplectomorphisms $Sp(4,\mathbb{R})$. It is generated by the spinorial realization of the conformal algebra $\mathfrak{so}(2,3)$ considered in…

Mathematical Physics · Physics 2025-06-16 Tekin Dereli , Philippe Nounahon , Todor Popov

Evidence that the fine structure constant, alpha, was different in an early epoch has recently been found in quasar (QSO) absorption spectra. An accurate laboratory measurement of alpha variation could help to distinguish between space and…

Atomic Physics · Physics 2016-09-08 E. J. Angstmann , V. A. Dzuba , V. V. Flambaum

Based on the adiabatic geometric phase concerning with density matrix[1] , we extend it to the sub-geometric phase in the non-adiabatic case. It is found that whatever the real part or imaginary part of the sub-geometric phase can play an…

Quantum Physics · Physics 2024-05-20 Zheng-Chuan Wang

The Dirac equation has been studied in which the Dirac matrices $\hat{\boldmath$\alpha$}, \hat\beta$ have space factors, respectively $f$ and $f_1$, dependent on the particle's space coordinates. The $f$ function deforms Heisenberg algebra…

Quantum Physics · Physics 2009-11-11 I. O. Vakarchuk

We consider full phase-space noncommutativity in the Dirac equation, and find that in order to preserve gauge invariance, configuration space noncommutativity must be dropped. The resulting space structure gives rise to a constant magnetic…

High Energy Physics - Theory · Physics 2015-05-28 Orfeu Bertolami , Raquel Queiroz

A spherically symmetric charged ideal fluid solution of Einstein field equation is given in the presence of the cosmological constant and two well known example of this type of solution is presented. If the matter is confined in a region,…

General Relativity and Quantum Cosmology · Physics 2007-11-30 N. Ozdemir

The adiabatic criterion, widely used in astronomical dynamics, is based on the harmonic oscillator. It asserts that the change in action under a slowly varying perturbation is exponentially small. Recent mathematical results precisely…

Astrophysics · Physics 2009-10-22 Martin D. Weinberg

We construct a Dirac equation in $\kappa$-Minkowski spacetime and analyse its implications. This $\kappa$-deformed Dirac equation is expanded as a power series involving derivatives with respect to commutative coordinates and the…

High Energy Physics - Theory · Physics 2011-07-28 E. Harikumar , M. Sivakumar , N. Srinivas

Hamiltonian systems with functionally dependent constraints (irregular systems), for which the standard Dirac procedure is not directly applicable, are discussed. They are classified according to their behavior in the vicinity of the…

High Energy Physics - Theory · Physics 2009-11-10 Olivera Miskovic , Jorge Zanelli

The time-dependent Dirac equation is solved using the three-dimensional Finite Difference-Time Domain (FDTD) method. The dynamics of the electron wave packet in a vector potential is studied in the arrangements associated with the…

Quantum Physics · Physics 2009-09-15 Neven Simicevic

We investigate consequences of allowing the Hilbert space of a quantum system to have a time-dependent metric. For a given possibly nonstationary quantum system, we show that the requirement of having a unitary Schreodinger time-evolution…

Quantum Physics · Physics 2015-06-26 Ali Mostafazadeh

A simple pseudo-Hamiltonian formulation is proposed for the linear inhomogeneous systems of ODEs. In contrast to the usual Hamiltonian mechanics, our approach is based on the use of non-stationary Poisson brackets, i.e. corresponding…

Quantum Physics · Physics 2009-11-11 V. G. Kupriyanov , S. L. Lyakhovich , A. A. Sharapov

The energy levels of hydrogen-like atom on a noncommutative phase space were studied in the framework of relativistic quantum mechanics. The leading order corrections to energy levels 2S_{1/2}, 2P_{1/2} and 2P_{3/2} were obtained by using…

Mathematical Physics · Physics 2012-02-14 Huseyin Masum , Sayipjamal Dulat , Mutallip Tohti

In adiabatic quantum computing the aim is to track an eigenstate as the Hamiltonian changes. In the usual setup this is achieved using the natural time-dependent Hamiltonian evolution of the system and the main technical tool is the…

Quantum Physics · Physics 2026-05-29 Joseph Cunningham , Jérémie Roland

We present the first detailed study of the kinematics of free relativistic particles whose symmetries are described by a quantum deformation of the de Sitter algebra, known as $q$-de Sitter Hopf algebra. The quantum deformation parameter is…

General Relativity and Quantum Cosmology · Physics 2016-06-29 Leonardo Barcaroli , Giulia Gubitosi

We employ the Dirac-Frenkel variational principle and multiple Davydov ansatz to study time-dependent fluorescence spectra of a driven qubit in the weak- to strong qubit-reservoir coupling regimes, where both the Rabi frequency and…

Quantum Physics · Physics 2020-08-25 Yiying Yan , Lipeng Chen , JunYan Luo , Yang Zhao

We consider a gravity dual description of time dependent, strongly interacting large-Nc N=4 SYM. We regard the gauge theory system as a fluid with shear viscosity. Our fluid is expanding in one direction following the Bjorken's picture that…

High Energy Physics - Theory · Physics 2009-11-11 Shin Nakamura , Sang-Jin Sin

We employ the framework of Bethe-Salpeter equation under Covariant Instantaneous Ansatz to study the leptonic decays of pseudoscalar mesons. The Dirac structure of hadron-quark vertex function $\Gamma $ is generalized to include various…

High Energy Physics - Phenomenology · Physics 2011-11-10 Shashank Bhatnagar , Shi-Yuan Li

Consider an open quantum system governed by a Gorini, Kossakowski, Sudarshan, Lindblad (GKSL) master equation with two times-scales: a fast one, exponentially converging towards a linear subspace of quasi-equilibria; a slow one resulting…

Quantum Physics · Physics 2023-09-08 François-Marie Le Régent , Pierre Rouchon

The semiclassical collapse of a sphere of quantized dust is studied. A Born-Oppenheimer decomposition is performed for the wave function of the system and the semiclassical limit is considered for the gravitational part. The method of…

General Relativity and Quantum Cosmology · Physics 2009-10-30 Roberto Casadio , Fabio Finelli , Giovanni Venturi