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Journal articles on the topic 'Free Dirac particles'

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Published: 3 June 2025

Last updated: 31 July 2025

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1

Faber, Manfried. "From Soft Dirac Monopoles to the Dirac Equation." Universe 8, no. 8 (2022): 387. http://dx.doi.org/10.3390/universe8080387.

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In the model of topological particles we have four types of topologically stable dual Dirac monopoles with soft cores and finite mass. We discuss the steps for getting a Dirac equation for these particles. We show for the free and the interacting case that we arrive at the Dirac equation in the limit, where the soft solitons approach singular dual Dirac monopoles.

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Emmanuel, D. K. Gazoya. "Superluminal Hydrogen Atom in a Constant Magnetic Field in (3+1)-dimensional Spacetime (II)." British Journal of Applied Science & Technology 21, no. 5 (2017): 1–13. https://doi.org/10.9734/BJAST/2017/34195.

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As has usually been the case in the tradition of some scientific novel ideas, we use the hydrogen atom as a “test particle”, in the context of superluminal dynamical system theory. In Paper (I) of this series, the fundamental effect of an applied external magnetic field on a transversely guided beam of hydrogen-like atoms is uncovered, that of transformation from spherical wave expansion into plane wave function. This leads to an unprecedented concept of a planar helical hydrogen field, with a continuum of linear momentum in (3+1)-dimensional spacetime. Thereupon, we investigate a possible “su

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3

Moalem, A., and A. Gersten. "Common Features of Free Particle Wave Functions in Curved Space-times." Journal of Physics: Conference Series 2482, no. 1 (2023): 012003. http://dx.doi.org/10.1088/1742-6596/2482/1/012003.

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Abstract Quantum equations for massless particles of any spin and for massive spin one-half particles are considered in curved space-times. It is demonstrated that in stationary axially symmetric space-times the angular wave functions up to a normalization function are the same as in a Minkowski space-time. The radial wave functions satisfy second order nonhomogeneous differential equations with three nonhomogeneous terms which depend in a unique form on the ratio of time to space curvatures. For a Dirac spin one-half particle, in addition to these three terms a fourth term which depends on th

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4

CHALUB, FABIO A. C. C. "On Huygens' principle for Dirac operators associated to electromagnetic fields." Anais da Academia Brasileira de Ciências 73, no. 4 (2001): 483–93. http://dx.doi.org/10.1590/s0001-37652001000400002.

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We study the behavior of massless Dirac particles, i.e., solutions of the Dirac equation with m = 0 in the presence of an electromagnetic field. Our main result (Theorem 1) is that for purely real or imaginary fields any Huygens type (in Hadamard's sense) Dirac operators is equivalent to the free Dirac operator, equivalence given by changes of variables and multiplication (right and left) by nonzero functions.

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5

COTĂESCU, ION I. "THE FREE DIRAC SPINORS OF THE SPIN BASIS ON THE DE SITTER EXPANDING UNIVERSE." Modern Physics Letters A 26, no. 22 (2011): 1613–19. http://dx.doi.org/10.1142/s0217732311036048.

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It is shown that on the de Sitter spacetime the global behavior of the free Dirac spinors in momentum representation is determined by several phase factors which are functions of momentum with special properties. Such suitable phase functions can be chosen for writing down the free Dirac quantum modes of the spin basis that are well-defined even for the particles at rest in the moving local charts where the modes of the helicity basis remain undefined. Under quantization, these modes lead to a basis in which the one-particle operators keep their usual forms apart from the energy operator which

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6

Gecim, Ganim. "GUP effect on thermodynamical properties of the noncommutative rotating BTZ black hole." Modern Physics Letters A 35, no. 25 (2020): 2050208. http://dx.doi.org/10.1142/s0217732320502089.

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In this paper, we investigated the quantum gravity effects on the thermal properties of the [Formula: see text]-dimensional noncommutative rotating Banados–Teitelboim–Zanelli (NCR-BTZ) black hole in the context of quantum tunneling of relativistic particles. These include Hawking temperature, the thermally local and global stability conditions, and the phase transitions. For this purpose, in the framework of the generalized uncertainty principle (GUP), we used the Hamilton–Jacobi approach to calculate the tunneling probability for a massive scalar, Dirac, and vector boson particles from the [F

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7

SÁNCHEZ, LAURA, IMELDA GALAVIZ, and HUGO GARCÍA-COMPEÁN. "DEFORMATION QUANTIZATION OF RELATIVISTIC PARTICLES IN ELECTROMAGNETIC FIELDS." International Journal of Modern Physics A 23, no. 11 (2008): 1757–90. http://dx.doi.org/10.1142/s0217751x08039360.

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The Weyl–Wigner–Moyal formalism for Dirac second-class constrained systems has been proposed recently as the deformation quantization of Dirac bracket. In this paper, after a brief review of this formalism, it is applied to the case of the relativistic free particle. Within this context, the Stratonovich–Weyl quantizer, Weyl correspondence, Moyal ⋆-product and Wigner function in the constrained phase-space are obtained. The recent Hamiltonian treatment for constrained systems, whose constraints depend explicitly on time, are used to perform the deformation quantization of the relativistic free

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8

Liang, Shi-Dong. "Dirac Theory in Noncommutative Phase Spaces." Physics 6, no. 3 (2024): 945–63. http://dx.doi.org/10.3390/physics6030058.

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Based on the position and momentum of noncommutative relations with a noncanonical map, we study the Dirac equation and analyze its parity and time reversal symmetries in a noncommutative phase space. Noncommutative parameters can be endowed with the Planck length and cosmological constant such that the noncommutative effect can be interpreted as an effective gauge potential or a (0,2)-type curvature associated with the Plank constant and cosmological constant. This provides a natural coupling between dynamics and spacetime geometry. We find that a free Dirac particle carries an intrinsic velo

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9

Moshinsky, M., and A. del Sol Mesa. "A relativistic cockroach nest." Canadian Journal of Physics 72, no. 7-8 (1994): 453–65. http://dx.doi.org/10.1139/p94-061.

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This paper does not deal with cockroaches running, as they sometimes seem to do, at a speed close to that of light. Rather its subject is a cockroach nest, i.e., a normally innocuous crack in the wall, but from which cockroaches start pouring out if some food is put near it. The physical problem concerns first the possible values of the energy of two relativistic free particles. An elementary classical calculation, in the center of mass frame of reference, shows that energy levels E appear at E ≥ 2mc2 and E ≤ −2mc2but also at E = 0. The latter is our crack in the wall. Turning to quantum mecha

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10

Rajput, B. S. "Quantum equations from Brownian motion." Canadian Journal of Physics 89, no. 2 (2011): 185–91. http://dx.doi.org/10.1139/p10-111.

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The Schrödinger free particle equation in 1+1 dimension describes second-order effects in ensembles of lattice random walks, in addition to its role in quantum mechanics, and its solutions represent the continuous limit of a property of ensembles of Brownian particles. In the present paper, the classical Schrödinger and Dirac equations have been derived from the Brownian motions of a particle, and it has been shown that the classical Schrödinger equation can be transformed into the usual Schrödinger quantum equation on applying the Heisenberg uncertainty principle between position and momentum

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Dariescu, Marina-Aura, and Ciprian Dariescu. "Heun Functions Describing Bosons and Fermions on Melvin’s Spacetime." Advances in High Energy Physics 2018 (June 11, 2018): 1–7. http://dx.doi.org/10.1155/2018/1953586.

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12

Yaguna, Carlos E., and Óscar Zapata. "Singlet Dirac dark matter streamlined." Journal of Cosmology and Astroparticle Physics 2024, no. 06 (2024): 049. http://dx.doi.org/10.1088/1475-7516/2024/06/049.

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Abstract We propose a new and compact realization of singlet Dirac dark matter within the WIMP framework. Our model replaces the standard Z 2 stabilizing symmetry with a Z 6, and uses spontaneous symmetry breaking to generate the dark matter mass, resulting in a much simplified scenario for Dirac dark matter. Concretely, we extend the Standard Model (SM) with just two new particles, a Dirac fermion (the dark matter) and a real scalar, both charged under the Z 6 symmetry. After acquiring a vacuum expectation value, the scalar gives mass to the dark matter and mixes with the Higgs boson, providi

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13

Dargys, Adolfas. "Majorana spinor from the point of view of geometric algebra." Lithuanian Journal of Physics 57, no. 1 (2017): 12–18. http://dx.doi.org/10.3952/physics.v57i1.3451.

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Majorana spinors are constructed in terms of the multivectors of relativistic Cl1,3 algebra. Such spinors are found to be multiplied by primitive idempotents which drastically change spinor properties. Running electronic waves are used to solve the real Dirac–Majorana equation transformed to Cl1,3 algebra. From the analysis of the solution it is concluded that free Majorana particles do not exist, because relativistic Cl1,3 algebra requires the massive Majorana particle to move with light velocity.

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14

Ugwu, Emmanuel. "Assessment of Zitterbewegung Interpretation for Free Particle Solution Using the Concept of Relativistic Wave." American Journal of Modern Physics 13, no. 3 (2024): 34–40. http://dx.doi.org/10.11648/j.ajmp.20241303.11.

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The Assessment of the interpretation of Zitterbewegung for free particle solution using various models has been carried out in this work where we firstly considered by using the free particle solution for which Dirac equation and projection operator were carried out.. ln this case, it was invariably revealed that the solution have two doubly degenerate eigenvalues representing positive and negative state that was further support by the analysis which was carried out using Heisenberg’s equation and the representation in relativistic velocity and semi-classical equation of motion for acceleratio

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15

Villalba, Victor M. "Separation of variables for the Klein–Gordon and Dirac equations in two-dimensional space-times with a null coordinate." Canadian Journal of Physics 68, no. 11 (1990): 1243–46. http://dx.doi.org/10.1139/p90-178.

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The separation of variables for the Klein–Gordon and Dirac equations, in the presence of electromagnetic fields, for a class of curvilinear coordinate systems with a null coordinate is presented. We show that these coordinates can be associated with a system with constant acceleration. Exact solutions for the free case and for a particle in a constant electric field are obtained. Finally, the quantum distribution of scalar massless particles in the accelerated frame of reference is computed.

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16

Qureshi, Tabish, and Ushba Rizwan. "Hanbury Brown–Twiss Effect with Wave Packets." Quanta 6, no. 1 (2017): 61. http://dx.doi.org/10.12743/quanta.v6i1.66.

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The Hanbury Brown–Twiss (HBT) effect, at the quantum level, is essentially an interference of one particle with another, as opposed to interference of a particle with itself. Conventional treatments of identical particles encounter difficulties while dealing with entanglement. A recently introduced label-free approach to indistinguishable particles is described, and is used to analyze the HBT effect. Quantum wave-packets have been used to provide a better understanding of the quantum interpretation of the HBT effect. The effect is demonstrated for two independent particles governed by Bose–Ein

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17

Nisticò, Giuseppe. "Group Theoretical Derivation of Consistent Free Particle Theories." Foundations of Physics 50, no. 9 (2020): 977–1007. http://dx.doi.org/10.1007/s10701-020-00364-2.

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AbstractThe difficulties of relativistic particle theories formulated by means of canonical quantization, such as those of Klein–Gordon and Dirac, ultimately led theoretical physicists to turn to quantum field theory to model elementary particle physics. In order to overcome these difficulties, the theories of the present approach are developed deductively from the physical principles that specify the system, without making use of canonical quantization. For a free particle these starting assumptions are invariance of the theory and covariance of position with respect to Poincaré transformatio

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18

Salesi, Giovanni. "Slower-Than-Light Spin-$\frac{1}{2}$ Particles Endowed with Negative Mass Squared." International Journal of Modern Physics A 12, no. 28 (1997): 5103–22. http://dx.doi.org/10.1142/s0217751x97002723.

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Extending in a straightforward way the standard Dirac theory, we study a quantum mechanical wave equation describing free spinning particles — which we propose to call Pseudotachyons (PT's) — which behave like tachyons in the momentum space (p2 = -m2), but like subluminal particles (v < c) in the ordinary space. This is allowed since, as it happens in every quantum theory for spin-[Formula: see text] particles, the momentum operator, -i ∇, (that is conserved), and the velocity operator α, (that is not), are independent operators, which refer to independent quantities: [Formula: see text]. A

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19

Dariescu, Marina-Aura, Ciprian Dariescu, and Cristian Stelea. "Massless fermions on static general prolate metrics and their Heun solutions." Modern Physics Letters A 35, no. 07 (2019): 2050036. http://dx.doi.org/10.1142/s0217732320500364.

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Employing a pseudo-orthonormal coordinate-free approach, we write down the Dirac equation in spacetimes with static general prolate metrics. As examples, we consider the electrically charged C-metric, the vacuum C-metric, the Reissner–Nordström and Schwarzschild spacetimes and the BBMB black hole and show that the solutions to the Dirac equations for particles in these spacetimes can be derived in terms of Heun’s general functions and their confluent and double confluent forms. By imposing boundary conditions to the radial solutions, the so-called resonant frequencies are obtained.

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20

Sheu, Tony W. H., Chenpeng Chiao, and Chinlong Huang. "Development of a Particle Interaction Kernel Function in MPS Method for Simulating Incompressible Free Surface Flow." Journal of Applied Mathematics 2011 (2011): 1–16. http://dx.doi.org/10.1155/2011/793653.

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We aimed to derive a kernel function that accounts for the interaction among moving particles within the framework of particle method. To predict a computationally more accurate moving particle solution for the Navier-Stokes equations, kernel function is a key to success in the development of interaction model. Since the smoothed quantity of a scalar or a vector at a spatial location is mathematically identical to its collocated value provided that the kernel function is chosen to be the Dirac delta function, our guideline is to derive the kernel function that is closer to the delta function a

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21

JABIN, PIERRE-EMMANUEL. "VARIOUS LEVELS OF MODELS FOR AEROSOLS." Mathematical Models and Methods in Applied Sciences 12, no. 07 (2002): 903–19. http://dx.doi.org/10.1142/s0218202502001957.

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Two limit behaviours of a simple model of aerosol are considered. The only force acting on aerosol particles is a friction due to the flow of gas. It is first proved that in the limit of an infinite friction coefficient, the particles are simply advected by the gas. Then we consider very dilute sprays of aerosol, i.e. with distribution functions which are monokinetic (Dirac mass in velocity). This approach leads to a macroscopic system with a free-boundary problem.

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22

Dariescu, Ciprian, Marina-Aura Dariescu, and Cristian Stelea. "Dirac Equation on the Kerr–Newman Spacetime and Heun Functions." Advances in High Energy Physics 2021 (April 14, 2021): 1–10. http://dx.doi.org/10.1155/2021/5512735.

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By employing a pseudoorthonormal coordinate-free approach, the Dirac equation for particles in the Kerr–Newman spacetime is separated into its radial and angular parts. In the massless case to which a special attention is given, the general Heun-type equations turn into their confluent form. We show how one recovers some results previously obtained in literature, by other means.

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23

JELLAL, AHMED, and BELLATI MALIKA. "FRACTIONAL QUANTUM HALL STATES IN GRAPHENE." International Journal of Geometric Methods in Modern Physics 07, no. 01 (2010): 143–64. http://dx.doi.org/10.1142/s0219887810003975.

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We quantum mechanically analyze the fractional quantum Hall effect in graphene. This will be done by building the corresponding states in terms of a potential governing the interactions and discussing other issues. More precisely, we consider a system of particles in the presence of an external magnetic field and take into account of a specific interaction that captures the basic features of the Laughlin series [Formula: see text]. We show that how its Laughlin potential can be generalized to deal with the composite fermions in graphene. To give a concrete example, we consider the SU(N) wavefu

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24

Kholodenko, Arkady L. "Maxwell-Dirac Isomorphism Revisited: From Foundations of Quantum Mechanics to Geometrodynamics and Cosmology." Universe 9, no. 6 (2023): 288. http://dx.doi.org/10.3390/universe9060288.

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Although electrons (fermions)and photons (bosons) produce the same interference patterns in the two-slit experiments, known in optics for photons since the 17th Century, the description of these patterns for electrons and photons thus far was markedly different. Photons are spin one, relativistic and massless particles while electrons are spin half massive particles producing the same interference patterns irrespective to their speed. Experiments with other massive particles demonstrate the same kind of interference patterns. In spite of these differences, in the early 1930s of the 20th Centur

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25

Lusanna, Luca. "The N- and 1-Time Classical Descriptions of N-Body Relativistic Kinematics and the Electromagnetic Interaction." International Journal of Modern Physics A 12, no. 04 (1997): 645–722. http://dx.doi.org/10.1142/s0217751x9700058x.

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Given N relativistic scalar free particles described by N mass-shell first class constraints in their 8N-dimensional phase space, their N-time description is obtained by means of a series of canonical transformations to a quasi-Shanmugadhasan basis adapted to the constraints. Then the same system is reformulated on spacelike hypersurfaces: the restriction to the family of hyperplanes orthogonal to the total timelike momentum gives rise to a covariant intrinsic 1-time formulation called the "rest-frame instant form" of dynamics. The relation between the N- and 1-time descriptions, the mass spec

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de Paoli, M. G., and D. P. Menezes. "Particle Yields in Heavy Ion Collisions and the Influence of Strong Magnetic Fields." Advances in High Energy Physics 2014 (2014): 1–13. http://dx.doi.org/10.1155/2014/479401.

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It is expected that the magnetic fields in heavy ion collisions are very high. In this work, we investigate the effects of a strong magnetic field on particle ratios within a thermal model of particle production. We model matter as a free gas of baryons and mesons under the influence of an external magnetic field varying from zero to30mπ2through an χ2fitting to some data sets of the STAR experiment. For this purpose, we use the Dirac, Rarita-Schwinger, Klein-Gordon, and Proca equations subject to magnetic fields in order to obtain the energy expressions and the degeneracy for spin 1/2, spin 3/

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27

Vladimirov, Yu S., and A. V. Solov'ev. "Generalized Dirac equations for free particles in binary geometrical physics. I. Rank (3,3;b) structure." Russian Physics Journal 35, no. 6 (1992): 533–37. http://dx.doi.org/10.1007/bf00559176.

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Vladimirov, Yu S., and A. V. Solov'ev. "Generalized Dirac equations for free particles in binary geometrical physics. II. Rank (4,4;b) structure." Russian Physics Journal 35, no. 6 (1992): 537–40. http://dx.doi.org/10.1007/bf00559177.

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29

Agafonov, A. I. "Massless Composite Bosons Formed by the Coupled Electron-Positron Pairs and Two-Photon Angular Correlations in the Colliding Beam Reaction e-e+→Bγγ with Emission of the Massless Boson". Advances in High Energy Physics 2018 (24 червня 2018): 1–18. http://dx.doi.org/10.1155/2018/6137380.

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The approach in which the electron and positron are treated as ordinary, different particles, each being characterized by the complete set of the Dirac plane waves, is examined. This completely symmetric representation that is beyond the standard QED makes it necessary to choose another solution of the Dirac equation for the free particle propagator as compared to that used currently. The Bethe-Salpeter equation with these particle propagators is solved in the ladder approximation. A new solution has been found represented by the massless composite bosons formed by the coupled electron-positro

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CHANG, ZHE, and HAN-YING GUO. "SYMMETRY REALIZATION, POISSON KERNEL AND THE AdS/CFT CORRESPONDENCE." Modern Physics Letters A 15, no. 06 (2000): 407–15. http://dx.doi.org/10.1142/s0217732300000396.

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Two kinds of realizations of symmetry on classical domains or the Euclidean version of AdS space are used to study AdS/CFT correspondence. Mass of free particles is defined as an AdS group invariant, the Klein–Gordon and Dirac equations for relativistic particles in the AdS space are set up as a simple mimic in the case of Minkowskian space. The bulk-boundary propagator on the AdS space is given by the Poisson kernel. Theorems on the Poisson kernel guarantee the existence and sole of the bulk-boundary propagator. The propagator is used to calculate correlators of the theories that live on the

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Kassandrov, Vladimir V., and Nina V. Markova. "Relativistic generalization of the Schrödinger-Newton model for the wavefunction reduction." International Journal of Modern Physics A 35, no. 02n03 (2020): 2040017. http://dx.doi.org/10.1142/s0217751x20400175.

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We consider the model of the self-gravity driven spontaneous wavefunction reduction proposed by L. Diosi, R. Penrose et al. and based on a self-consistent system of Schrödinger and Poisson equations. An analogous system of coupled Dirac and Maxwell-like equations is proposed as a relativization. Regular solutions to the latter form a discrete spectrum in which all the “active” gravitational masses are always positive, and approximately equal to inertial masses and to the mass [Formula: see text] of the quanta of Dirac field up to the corrections of order [Formula: see text]. Here [Formula: see

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Jentschura, U. D., and B. J. Wundt. "From Generalized Dirac Equations to a Candidate for Dark Energy." ISRN High Energy Physics 2013 (March 6, 2013): 1–21. http://dx.doi.org/10.1155/2013/374612.

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We consider extensions of the Dirac equation with mass terms m1+iγ5m2 and im1+γ5m2. The corresponding Hamiltonians are Hermitian and pseudo-Hermitian (γ5 Hermitian), respectively. The fundamental spinor solutions for all generalized Dirac equations are found in the helicity basis and brought into concise analytic form. We postulate that the time-ordered product of field operators should yield the Feynman propagator (iϵ prescription), and we also postulate that the tardyonic as well as tachyonic Dirac equations should have a smooth massless limit. These postulates lead to sum rules that connect

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SIGISMONDI, COSTANTINO, SIMONETTA FILIPPI, REMO RUFFINI, and LUIS ALBERTO SÁNCHEZ. "DAMPING TIME AND STABILITY OF DENSITY FERMION PERTURBATIONS IN THE EXPANDING UNIVERSE." International Journal of Modern Physics D 10, no. 05 (2001): 663–79. http://dx.doi.org/10.1142/s0218271801001190.

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The classic problem of the growth of density perturbations in an expanding Newtonian universe is revisited following the work of Bisnovatyi-Kogan and Zel'dovich. We propose a more general analytical approach: a system of free particles satisfying semidegenerate Fermi–Dirac statistics on the background of an exact expanding solution is examined in the linear approximation. This differs from the corresponding work of Bisnovatyi-Kogan and Zel'dovich where classical particles fulfilling Maxwell–Boltzmann statistics were considered. The solutions of the Boltzmann equation are obtained by the method

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KOSYAKOV, B. P. "SELF-ACCELERATED UNIVERSE." International Journal of Modern Physics A 20, no. 11 (2005): 2459–64. http://dx.doi.org/10.1142/s0217751x05024778.

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It is widely believed that the large redshifts for distant supernovae are due to the vacuum energy dominance, which is responsible for the anti-gravitation effect. A tacit assumption is that particles move along geodesics for the background metric. This is in the same spirit as the consensus regarding the uniform Galilean motion of a free electron. However, apart from the Galilean solution, there is a self-accelerated solution to the Lorentz–Dirac equation governing the behavior of a radiating electron. Likewise, a runaway solution to the entire system of equations, both gravitation and matter

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Bittencourt, V. A. S. V., M. Blasone, and G. Zanfardino. "Chiral and flavor oscillations in quantum field theory: an overview." Journal of Physics: Conference Series 3017, no. 1 (2025): 012026. https://doi.org/10.1088/1742-6596/3017/1/012026.

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Abstract Flavor is not conserved during the free evolution of mixed neutrinos, leading to flavor oscillations. In addition, non-relativistic massive neutrinos also undergo chiral oscillations. While both phenomena, and their interplay, have been described in first quantization using the Dirac equation, a unified quantum field theory (QFT) framework remains lacking. In this work, we review the description of flavor oscillations and of chiral oscillations in QFT: in both cases, Bogoliubov transformations are involved in the definition of the chiral and flavor states produced in weak interaction

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Nanni, L. "Superluminal Tunneling of a Relativistic Half-Integer Spin Particle Through a Potential Barrier." International Journal of Modern Physics: Conference Series 47 (January 2018): 1860102. http://dx.doi.org/10.1142/s2010194518601023.

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This paper investigates the problem of a relativistic Dirac half-integer spin free particle tunneling through a rectangular quantum-mechanical barrier. If the energy difference between the barrier and the particle is positive, and the barrier width is large enough, there is proof that the tunneling may be superluminal. For first spinor components of particle and antiparticle states, the tunneling is always superluminal regardless the barrier width. Conversely, the second spinor components of particle and antiparticle states may be either subluminal or superluminal depending on the barrier widt

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Nanni, Luca. "Superluminal tunneling of a relativistic half-integer spin particle through a potential barrier." Open Physics 15, no. 1 (2017): 682–91. http://dx.doi.org/10.1515/phys-2017-0080.

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AbstractThis paper investigates the problem of a relativistic Dirac half-integer spin free particle tunneling through a rectangular quantum-mechanical barrier. If the energy difference between the barrier and the particle is positive, and the barrier width is large enough, there is proof that the tunneling may be superluminal. For first spinor components of particle and antiparticle states, the tunneling is always superluminal regardless the barrier width. Conversely, the second spinor components of particle and antiparticle states may be either subluminal or superluminal depending on the barr

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Ching, C. L., C. X. Yeo, and W. K. Ng. "Nonrelativistic anti-Snyder model and some applications." International Journal of Modern Physics A 32, no. 02n03 (2017): 1750009. http://dx.doi.org/10.1142/s0217751x17500099.

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In this paper, we examine the (2[Formula: see text]+[Formula: see text]1)-dimensional Dirac equation in a homogeneous magnetic field under the nonrelativistic anti-Snyder model which is relevant to doubly/deformed special relativity (DSR) since it exhibits an intrinsic upper bound of the momentum of free particles. After setting up the formalism, exact eigensolutions are derived in momentum space representation and they are expressed in terms of finite orthogonal Romanovski polynomials. There is a finite maximum number of allowable bound states [Formula: see text] due to the orthogonality of t

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Luongo, Orlando, and Stefano Mancini. "Entanglement in model-independent cosmological scenario." International Journal of Geometric Methods in Modern Physics 16, no. 08 (2019): 1950114. http://dx.doi.org/10.1142/s0219887819501147.

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We propose a model-independent approach to study entanglement creation due to the dynamics between two asymptotic quantum regimes in the framework of homogeneous and isotropic universe. We realize it by Padé expansion to reconstruct the functional form of scale factor, rather than postulating it a priori. This amounts to fix the Padé approximants constraining the free parameters in terms of current cosmic observations. Assuming fermions, we solve the Dirac equation for massive particles and we investigate entanglement entropy in terms of modes [Formula: see text] and mass [Formula: see text].

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Chen, Da-Ming, and Lin Wang. "Quantum Effects on Cosmic Scales as an Alternative to Dark Matter and Dark Energy." Universe 10, no. 8 (2024): 333. http://dx.doi.org/10.3390/universe10080333.

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The spin-torsion theory is a gauge theory approach to gravity that expands upon Einstein’s general relativity (GR) by incorporating the spin of microparticles. In this study, we further develop the spin-torsion theory to examine spherically symmetric and static gravitational systems that involve free-falling macroscopic particles. We posit that the quantum spin of macroscopic matter becomes noteworthy at cosmic scales. We further assume that the Dirac spinor and Dirac equation adequately capture all essential physical characteristics of the particles and their associated processes. A crucial a

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Delgado Acosta, E. G., V. M. Banda Guzmán та M. Kirchbach. "Gyromagnetic gs factors of the spin-1/2 particles in the (1/2+-1/2--3/2-) triad of the four-vector spinor, ψμ, irreducibility and linearity". International Journal of Modern Physics E 24, № 07 (2015): 1550060. http://dx.doi.org/10.1142/s0218301315500603.

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The gauged Klein–Gordon equation, extended by a gsσμνFμν/4 interaction, the contraction of the electromagnetic field strength tensor, Fμν, with the generators, σμν/2, of the Lorentz group in (1/2, 0) ⊕ (0, 1/2), and gs being the gyromagnetic factor, is examined with the aim to find out as to what extent it qualifies as a wave equation for general relativistic spin-1/2 particles transforming as (1/2, 0) ⊕ (0, 1/2) and possibly distinct from the Dirac fermions. This equation can be viewed as the generalization of the gs = 2 case, known under the name of the Feynman–Gell-Mann equation, the only o

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Tóth, Gábor Zsolt. "Higher spin fields with reversed spin-statistics relation." International Journal of Modern Physics A 29, no. 23 (2014): 1450129. http://dx.doi.org/10.1142/s0217751x14501292.

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A construction of massive free fields with arbitrary spin and reversed spin-statistics relation is presented. The main idea of the construction is to consider fields that transform according to representations of the Lorentz group that are doubled in comparison with the representations according to which normal (physical) fields transform. This allows the definition of opposite commutation properties for these fields, while the spin of the particles they describe remains unchanged. The correspondence established by the construction between fields obeying normal and reversed spin-statistics rel

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SALESI, GIOVANNI. "NON-NEWTONIAN MECHANICS." International Journal of Modern Physics A 17, no. 03 (2002): 347–74. http://dx.doi.org/10.1142/s0217751x02005797.

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The classical motion of spinning particles can be described without recourse to particular models or special formalisms, and without employing Grassmann variables or Clifford algebras, but simply by generalizing the usual spinless theory. We only assume the invariance with respect to the Poincaré group; and only requiring the conservation of the linear and angular momenta, we derive the zitterbewegung, namely the decomposition of the four-velocity in the usual Newtonian constant term pμ/m and in a non-Newtonian time-oscillating spacelike term. Consequently, free classical particles do not obey

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dos Santos, Alessandro L. R., Denis Dalmazi, and Wayne de Paula. "Hamiltonian analysis and positivity of a new massive spin-2 model." Classical and Quantum Gravity 39, no. 3 (2022): 035013. http://dx.doi.org/10.1088/1361-6382/ac4380.

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Abstract Recently a new model has been proposed to describe free massive spin-2 particles in D dimensions in terms of a non symmetric rank-2 tensor e μν and a mixed symmetry tensor B μ[αβ]. The model is invariant under linearized diffeomorphisms without Stueckelberg fields. It resembles a spin-2 version of the topologically massive spin-1 BF model (Cremmer–Scherk model). Here we apply the Dirac–Bergmann procedure in order to identify all Hamiltonian constraints and perform a complete counting of degrees of freedom. In D = 3 + 1 we find 5 degrees of freedom corresponding to helicities ±2, ±1, 0

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PANTELIDES, SOKRATES T. "A NEW THEORY OF ELECTROMAGNETIC, WEAK AND STRONG INTERACTIONS." International Journal of Modern Physics E 11, no. 03 (2002): 177–210. http://dx.doi.org/10.1142/s0218301302000806.

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The Higgs mechanism for imparting masses to gauge bosons and matter particles is obviated by showing that Yang–Mills gauge bosons have intrinsic nonzero masses (rest-frame energies) from self-interactions. Electroweak (EW) mixing is ruled out because it produces a photon field that is massive, carries EW charge, and does not satisfy Maxwell's equations. Other fundamental difficulties of the Standard Model are identified. A new gauge theory of electromagnetic, weak and strong interactions is derived from the Dirac equation with no other postulates and no free parameters. The three forces are in

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Salas, P., M. A. Solís, M. Fortes, and F. J. Sevilla. "Thermodynamic properties of underdoped YBa2Cu3O6+x cuprates for several doping values." International Journal of Modern Physics B 31, no. 13 (2017): 1750100. http://dx.doi.org/10.1142/s0217979217501004.

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We report the thermodynamic properties of cuprate superconductors YBa2Cu3O[Formula: see text], with [Formula: see text] ranging from underdoped ([Formula: see text]) to optimally doped ([Formula: see text]) regions. We model cuprates as a boson–fermion gas mixture immersed in a layered structure, which is generated via a Dirac-comb potential applied in the perpendicular direction to the CuO2 planes, while the particles move freely in the other two directions. The optimal system parameters, namely, the planes’ impenetrability and the paired-fermion fraction, are obtained by minimizing the Helmh

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Liang, Shi-Dong, and Matthew J. Lake. "An Introduction to Noncommutative Physics." Physics 5, no. 2 (2023): 436–60. http://dx.doi.org/10.3390/physics5020031.

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Noncommutativity in physics has a long history, tracing back to classical mechanics. In recent years, many new developments in theoretical physics, and in practical applications rely on different techniques of noncommutative algebras. In this review, we introduce the basic concepts and techniques of noncommutative physics in a range of areas, including classical physics, condensed matter systems, statistical mechanics, and quantum mechanics, and we present some important examples of noncommutative algebras, including the classical Poisson brackets, the Heisenberg algebra, Lie and Clifford alge

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Rajaram, R., B. Castellani, and A. N. Wilson. "Advancing Shannon Entropy for Measuring Diversity in Systems." Complexity 2017 (2017): 1–10. http://dx.doi.org/10.1155/2017/8715605.

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From economic inequality and species diversity to power laws and the analysis of multiple trends and trajectories, diversity within systems is a major issue for science. Part of the challenge is measuring it. Shannon entropy H has been used to rethink diversity within probability distributions, based on the notion of information. However, there are two major limitations to Shannon’s approach. First, it cannot be used to compare diversity distributions that have different levels of scale. Second, it cannot be used to compare parts of diversity distributions to the whole. To address these limita

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HONG, SOON-TAE, WON TAE KIM, and YOUNG-JAI PARK. "IMPROVED DIRAC QUANTIZATION OF A FREE PARTICLE." Modern Physics Letters A 15, no. 31 (2000): 1915–22. http://dx.doi.org/10.1142/s0217732300002450.

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In the framework of Dirac quantization with second-class constraints, a free particle moving on the surface of a (d-1)-dimensional sphere has an ambiguity in the energy spectrum due to the arbitrary shift of canonical momenta. We explicitly show that this spectrum obtained by the Dirac method is consistent with the result of the Batalin–Fradkin–Tyutin formalism, which is an improved Dirac method, at the level of the first-class constraint by fixing the ambiguity, and discuss its physical consequences.

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MIRJALILI, ABOLFAZL, MAJID DEHGHANI, and MOHAMMAD MEHDI YAZDANPANAH. "PARTON DENSITIES WITH THE QUARK LINEAR POTENTIAL IN THE STATISTICAL APPROACH." International Journal of Modern Physics A 28, no. 18 (2013): 1350089. http://dx.doi.org/10.1142/s0217751x13500899.

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The statistical approach is used to calculate the parton distribution functions (PDFs) of the nucleon. At first it is assumed that the partons are free particles and the light-front kinematic variables are employed to extract the Bjorken x-dependence of the PDFs. These PDFs are used to evaluate the combinations of the sea quarks such as [Formula: see text]. As our first attempt to improve the result, we make the statistical parameters to depend on Q2, using different values of Gottfried sum rule. The related results are indicating better behavior by accessing to the PDFs while they contain the

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