A generalized statistical complexity based on Rényi entropy of a noncommutative anisotropic oscillator in a homogeneous magnetic field

2019 ◽  
Vol 34 (20) ◽  
pp. 1950105 ◽  
Author(s):  
Debraj Nath ◽  
Piu Ghosh
Keyword(s):  
Magnetic Field ◽  
Homogeneous Magnetic Field ◽  
Renyi Entropy ◽  
Rényi Entropy ◽  
Monotone Functions ◽  
Statistical Complexity ◽  
The Magnetic Field ◽  
Anisotropic Oscillator ◽  
Do So ◽  
Noncommutative Parameter

We calculate the shape Rényi and generalized Rényi complexity of a noncommutative anisotropic harmonic oscillator in a homogeneous magnetic field. To do so, we first obtain the Rényi entropy in position and momentum spaces of the exact normalized wave functions. We observe that shape Rényi and generalized Rényi complexities are monotone functions of noncommutative parameter ([Formula: see text]) in some short range in position space. We analyze the effect of the noncommutative parameter, the magnetic field and the anisotropy on shape Rényi and generalized Rényi complexities.

scholarly journals Finite Element Analysis of Magnetic Field Exciter for Direct Testing of Magnetocaloric Materials’ Properties

Energies ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2792
Author(s):  
Wieslaw Lyskawinski ◽  
Wojciech Szelag ◽  
Cezary Jedryczka ◽  
Tomasz Tolinski
Keyword(s):  
Magnetic Field ◽  
Finite Element ◽  
Magnetic Circuit ◽  
Homogeneous Magnetic Field ◽  
Element Analysis ◽  
Mcm Testing ◽  
Testing Region ◽  
Magnetocaloric Materials ◽  
Field Excitation ◽  
The Magnetic Field

The paper presents research on magnetic field exciters dedicated to testing magnetocaloric materials (MCMs) as well as used in the design process of magnetic refrigeration systems. An important element of the proposed test stand is the system of magnetic field excitation. It should provide a homogeneous magnetic field with a controllable value of its intensity in the MCM testing region. Several concepts of a magnetic circuit when designing the field exciters have been proposed and evaluated. In the MCM testing region of the proposed exciters, the magnetic field is controlled by changing the structure of the magnetic circuit. A precise 3D field model of electromagnetic phenomena has been developed in the professional finite element method (FEM) package and used to design and analyze the exciters. The obtained results of the calculations of the magnetic field distribution in the working area were compared with the results of the measurements carried out on the exciter prototype. The conclusions resulting from the conducted research are presented and discussed.

scholarly journals Magnetic Rayleigh–Taylor instability at a contact discontinuity with an oblique magnetic field

2020 ◽  
Vol 634 ◽  
pp. A96
Author(s):  
E. Vickers ◽  
I. Ballai ◽  
R. Erdélyi
Keyword(s):  
Magnetic Field ◽  
Growth Rate ◽  
Dispersion Relation ◽  
Contact Discontinuity ◽  
Homogeneous Magnetic Field ◽  
Taylor Instability ◽  
Wide Range ◽  
Rayleigh Taylor Instability ◽  
The Magnetic Field ◽  
Theoretical Results

Aims. We investigate the nature of the magnetic Rayleigh–Taylor instability at a density interface that is permeated by an oblique homogeneous magnetic field in an incompressible limit. Methods. Using the system of linearised ideal incompressible magnetohydrodynamics equations, we derive the dispersion relation for perturbations of the contact discontinuity by imposing the necessary continuity conditions at the interface. The imaginary part of the frequency describes the growth rate of waves due to instability. The growth rate of waves is studied by numerically solving the dispersion relation. Results. The critical wavenumber at which waves become unstable, which is present for a parallel magnetic field, disappears because the magnetic field is inclined. Instead, waves are shown to be unstable for all wavenumbers. Theoretical results are applied to diagnose the structure of the magnetic field in prominence threads. When we apply our theoretical results to observed waves in prominence plumes, we obtain a wide range of field inclination angles, from 0.5° up to 30°. These results highlight the diagnostic possibilities that our study offers.

Analysis of Vibration Characteristics of Magnetorheological Elastomer Sandwich Beam under Non-Homogeneous Magnetic Field

2011 ◽  
Vol 101-102 ◽  
pp. 202-206 ◽  
Author(s):  
Guo Liang Hu ◽  
Miao Guo ◽  
Wei Hua Li
Keyword(s):  
Magnetic Field ◽  
Natural Frequency ◽  
Sandwich Beam ◽  
Homogeneous Magnetic Field ◽  
Experimental Results ◽  
Magnetorheological Elastomer ◽  
Test Rig ◽  
Thin Aluminum ◽  
Set Up ◽  
The Magnetic Field

In this study, the MRE was manufactured, and the sandwich beam was also fabricated by treating with MRE between two thin aluminum layers. The experiment test rig was set up to investigate the vibration response of the MRE sandwich beam under non-homogeneous magnetic field. The experimental results show that the MRE sandwich beam had the capabilities of left shifting first natural frequency when the magnetic field was increased in the activated regions. It is also obvious that the first natural frequency of the MRE sandwich beam decreased as the magnetic field that applied on the beam was moved from the clamped end of the beam to the free end of the beam.

scholarly journals DYNAMO EFFECTS IN MAGNETIZED IDEAL PLASMA COSMOLOGIES

2008 ◽  
Vol 23 (11) ◽  
pp. 1697-1710 ◽  
Author(s):  
KOSTAS KLEIDIS ◽  
APOSTOLOS KUIROUKIDIS ◽  
DEMETRIOS PAPADOPOULOS ◽  
LOUKAS VLAHOS
Keyword(s):  
Magnetic Field ◽  
Cosmological Model ◽  
Homogeneous Magnetic Field ◽  
Mhd Equations ◽  
Cosmological Perturbations ◽  
Gravitational Instabilities ◽  
Ideal Magnetohydrodynamic ◽  
The Magnetic Field ◽  
Ideal Plasma ◽  
The Ideal

The excitation of cosmological perturbations in an anisotropic cosmological model and in the presence of a homogeneous magnetic field has been studied, using the ideal magnetohydrodynamic (MHD) equations. In this case, the system of partial differential equations which governs the evolution of the magnetized cosmological perturbations can be solved analytically. Our results verify that fast-magnetosonic modes propagating normal to the magnetic field, are excited. But, what is most important, is that, at late times, the magnetic-induction contrast(δB/B) grows, resulting in the enhancement of the ambient magnetic field. This process can be particularly favored by condensations, formed within the plasma fluid due to gravitational instabilities.

scholarly journals Влияние нелинейности закона намагничивания феррожидкости на неустойчивость Кельвина--Гельмгольца

2021 ◽  
Vol 91 (8) ◽  
pp. 1199
Author(s):  
В.М. Коровин
Keyword(s):  
Magnetic Field ◽  
Field Intensity ◽  
Relative Velocity ◽  
Gas Flow ◽  
Magnetic Field Intensity ◽  
Homogeneous Magnetic Field ◽  
Helmholtz Instability ◽  
Magnetization Saturation ◽  
The Magnetic Field ◽  
Stability Area

We study Kelvin-Helmholtz instability which develops when a homogenous gas flow is moving over a horizontal surface of a ferrofluid of given physical properties moving in the same direction, in presence of a homogeneous magnetic field parallel to this direction. Magnetic field intensity range includes the values that correspond to the interval where magnetization curve reaches magnetization saturation level. Stability area is constructed in the “magnetic field intensity – dimensionless relative velocity of fluids” parameter plane.

scholarly journals Quantum Speed Limit for Relativistic Spin-0 and Spin-1 Bosons on Commutative and Noncommutative Planes

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Kang Wang ◽  
Yu-Fei Zhang ◽  
Qing Wang ◽  
Zheng-Wen Long ◽  
Jian Jing
Keyword(s):  
Magnetic Field ◽  
Lorentz Invariance ◽  
Wave Packets ◽  
Relativistic Quantum ◽  
Homogeneous Magnetic Field ◽  
Relativistic Quantum Mechanics ◽  
Speed Of Light ◽  
Initial State ◽  
The Magnetic Field ◽  
Noncommutative Plane

Quantum speed limits of relativistic charged spin-0 and spin-1 bosons in the background of a homogeneous magnetic field are studied on both commutative and noncommutative planes. We show that, on the commutative plane, the average speeds of wave packets along the radial direction during the interval in which a quantum state is evolving from an initial state to the orthogonal final one can not exceed the speed of light, regardless of the intensities of the magnetic field. However, due to the noncommutativity, the average speeds of the wave packets on noncommutative plane will exceed the speed of light in vacuum provided the intensity of the magnetic field is strong enough. It is a clear signature of violating Lorentz invariance in the relativistic quantum mechanics region.

scholarly journals Magnetic Field Decay in the Non-superfluid Regions of Neutron Star Cores

1994 ◽  
Vol 147 ◽  
pp. 591-595
Author(s):  
A.G. Muslimov ◽  
H.M. Van Horn
Keyword(s):  
Magnetic Field ◽  
Neutron Star ◽  
Simple Model ◽  
Homogeneous Magnetic Field ◽  
Rapid Decline ◽  
Cooling History ◽  
Poloidal Magnetic Field ◽  
Field Decay ◽  
The Magnetic Field ◽  
Urca Process

AbstractWe consider a simple model for the evolution of a poloidal magnetic field initally trapped in a region containing normal npe matter within the outerliquid core of a neutron star. We have performed numerical computations for neutron stars with masses of 1.4, 1.6, and 1.7 M⊙ that undergo very rapid cooling due to the direct Urca process. Because the timescale for the magnetic field decay is directly proportional to T2, such a cooling history produces a rapid decline in the magnetic-field strength B, even for B as low as ∼ 1012 G. In particular, we show that an initially quasi-homogeneous magnetic field of strength B = 1012 G declines during the first ∼ 1 Myr.

Die Energiebilanz eines Wasserstoffbogens in axialem Magnetfeld

1965 ◽  
Vol 20 (3) ◽  
pp. 475-484 ◽  
Author(s):  
Udo Heidrich
Keyword(s):  
Magnetic Field ◽  
Electrical Power ◽  
Homogeneous Magnetic Field ◽  
Hydrogen Atmosphere ◽  
Arc Length ◽  
Radial Temperature ◽  
Cylindrically Symmetric ◽  
Radiation Losses ◽  
Current Voltage ◽  
The Magnetic Field

The numerical solution of the energy balance of a cylindrically symmetric hydrogen arc immersed in an axial, strong, homogeneous magnetic field led to the current-voltage-characteristic and the radial temperature distribution. Three types of arc models were used, each with different assumptions on radiation losses. The results show that, by the reduction of the thermal conductivity perpendicular to the magnetic field for a fully ionized plasma, the necessary electrical power is diminished for temperatures along the axis higher than about 2·104°K. For example, an arc with 1 cm radius in a hydrogen atmosphere of 5 · 104 dyne/cm2, in an external magnetic field of 20 kGauss, a temperature along the axis of 105°K requires about 3,5 kW per cm arc length. Of this, radiation losses account for about 0,5 kW per cm. However, without a superimposed magnetic field the electrical power is about 200 kW per cm.

The search for electromagnetic induction, 1820-1831

1965 ◽  
Vol 20 (2) ◽  
pp. 184-219 ◽  
Keyword(s):  
Magnetic Field ◽  
Electromagnetic Induction ◽  
The United States ◽  
Single Wire ◽  
Electricity And Magnetism ◽  
Magnetic Meridian ◽  
The Right ◽  
The University ◽  
The Magnetic Field ◽  
Do So

Oersted´s discovery in 1820 of the magnetic field that surrounds a conductor during the passage of an electric current, aroused a wave of interest among men of science in England, France, Germany, Italy, and the United States. The apparatus required to verify his results was easily put together, and anyone who cared to do so could see for himself the nature of the indissoluble connexion between electricity and magnetism, which, though long suspected and vaguely adumbrated, was now precisely defined and made a permanent portion of the corpus of science. As one subsequent discovery after another was announced from various places, the recognition became widespread that a large and unexploited field for investigations and applications had been opened up. Only one week after word of Oersted’s experiment reached Paris, Ampere discovered that two parallel wires that carry parallel currents attract each other. Less than two months after Oersted’s publication, J. S. C. Schweigger (1779-1857), at the University of Halle, reasoned that if the current in a single wire held above the compass needle would deflect the needle to the right, while the same wire placed beneath the needle would deflect it to the left, one turn of wire, placed around the needle in the plane of the magnetic meridian, would exert twice the deflecting force of a single wire; and a coil made of ten turns of insulated wire would exert twenty times the force.

Sign in / Sign up

Export Citation Format

Share Document