Universal Journal of Physics Research
Open Access September 26, 2023 17 pages 1616 views 228 downloads

Charged Stellar Model with Generalized Chaplygin Equation of State Consistent with Observational Data

Universal Journal of Physics Research 2023, 2(1), 748. DOI: 10.31586/ujpr.2023.748
Abstract
In this paper, we found a new model for a compact star with charged anisotropic matter distribution considering the generalized Chaplygin equation of state. The Einstein-Maxwell field equations have been solved with a particular form of metric potential and electric field intensity. The plots show that physical variables such as radial pressure, energy density, charge density, anisotropy, radial
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In this paper, we found a new model for a compact star with charged anisotropic matter distribution considering the generalized Chaplygin equation of state. The Einstein-Maxwell field equations have been solved with a particular form of metric potential and electric field intensity. The plots show that physical variables such as radial pressure, energy density, charge density, anisotropy, radial speed sound, and the mass are fully well defined and are regular in the star's interior. We obtained models consistent with stellar objects such as GJ 832, LHS 43, SAO 81292, GJ 380, GJ 412, and SAO 62377.Full article
Article
Open Access August 30, 2023 5 pages 769 views 171 downloads

Spin Structures and non-Relativistic Spin Operators

Universal Journal of Physics Research 2023, 2(1), 664. DOI: 10.31586/ujpr.2023.664
Abstract
In Quantum Physics, the spin and angular momentum operators are magnitudes introduced by means of a vector transformation law. However, interpreting the eigenvalues of its Z "components" as projections on said axis leads to certain contradictions supposedly avoided by a mandatory (presented as a freely selected) Z's orientation. It is shown that an oriented physical space almost forces us to
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In Quantum Physics, the spin and angular momentum operators are magnitudes introduced by means of a vector transformation law. However, interpreting the eigenvalues of its Z "components" as projections on said axis leads to certain contradictions supposedly avoided by a mandatory (presented as a freely selected) Z's orientation. It is shown that an oriented physical space almost forces us to project the angular momentum's and spin's eigenvalues onto its orientation's 3-form, which sidesteps entering into inconsistencies. The final conclusion is that this "rare" magnitude called spin, downright naturally comes in and plays thanks to the orientation of our three-dimensional space.Full article
Communication
Open Access February 09, 2023 19 pages 720 views 502 downloads

Two-Mode Sub harmonic Generator Coupled to Thermal Reservoir

Universal Journal of Physics Research 2023, 2(1), 564. DOI: 10.31586/ujpr.2023.564
Abstract
In this article, our investigation to study squeezing and statistical properties of the light by a two mode sub harmonic generator coupled to thermal reservoir via a single port-mirror. The equation of motion answers are then used to calculate the mean photon number, photon number variance, and quadrature variance for two mode cavity light. However, we have found that the degree of squeezing is
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In this article, our investigation to study squeezing and statistical properties of the light by a two mode sub harmonic generator coupled to thermal reservoir via a single port-mirror. The equation of motion answers are then used to calculate the mean photon number, photon number variance, and quadrature variance for two mode cavity light. However, we have found that the degree of squeezing is indeed affected by the present of thermal light. The mean photon number of the system under consideration increases with increasing n-.Full article
Review Article
Open Access February 08, 2023 18 pages 514 views 222 downloads

Entangled Photon Generation from a Three-Level Laser with a Parametric Amplifier and Coupled to a Thermal Reservoir

Universal Journal of Physics Research 2023, 2(1), 507. DOI: 10.31586/ujpr.2023.507
Abstract
In this article the investigation of squeezing and statistical properties of light resulting by a non-degenerate three-level laser with the parametric amplifier and coupled to a thermal reservoir have been occurred. With the aid of master equation, stochastic differential equations were obtained. Applying solutions of resulting differential equations, quadrature variance, the mean and variance of
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In this article the investigation of squeezing and statistical properties of light resulting by a non-degenerate three-level laser with the parametric amplifier and coupled to a thermal reservoir have been occurred. With the aid of master equation, stochastic differential equations were obtained. Applying solutions of resulting differential equations, quadrature variance, the mean and variance of photon number, the photon number correlation are calculated. However, the two-mode driving light has no effect on the squeezing properties of the cavity modes. On the other hand, parametric amplifier and thermal reservoir increase the mean and variance of photon number. Furthermore, employing the same solutions, we also obtain anti normally ordered characteristic function defined in the Heisenberg picture. For a linear gain coefficient of (A = 100), for a cavity damping constant of K= 0:8, µ = 0 and for thermal reservoir th = 0, the maximum intra cavity photon entanglement is found at steady state and at threshold to be 60%.Full article
Review Article
Open Access November 24, 2022 11 pages 558 views 171 downloads

Relativistic Radial Density Theory (RRDT)

Universal Journal of Physics Research 2022, 1(1), 500. DOI: 10.31586/ujpr.2022.500
Abstract
Starting with Planck scale it is developed the Relativistic Radial Density Theory (RRDT). In this theory, the Planck and gravitational parameters can be described as the functions of the radial mass (energy) density value. This density is maximal at the minimal radius and minimal at the maximal radius. This conclusion is based on the fact that the ratio of Planck mass and Planck length
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Starting with Planck scale it is developed the Relativistic Radial Density Theory (RRDT). In this theory, the Planck and gravitational parameters can be described as the functions of the radial mass (energy) density value. This density is maximal at the minimal radius and minimal at the maximal radius. This conclusion is based on the fact that the ratio of Planck mass and Planck length (radius) is constant. These radiuses can be described as the function of the energy conservation constant κ. Using RRDT, it is possible to develop the connections between Planck’s and gravitational parameters as function of the maximal and minimal radial mass (energy) density values. In that sense, the gravitational length, time, energy and temperature can be presented as the function of the Planck length, time, energy and temperature, respectively. This opens possibility to merge of Quantum Field Theory (QFT) and the General Theory of Relativity (GTR) at the quantum scale in gravitational field. The existence of the maximal radial mass (energy) density value at the minimal radius in gravitational field means that no singularity in that field. Further, the existence of the minimal radial mass (energy) density value at the maximal radius in gravitational field means that no infinity in that field. It follows the postulation: the most minimal radius in a gravitational field belongs to the minimal mass (energy). Since the Planck mass is not the minimal mass in space-time, the Planck length/radius is not the minimal length/radius in the space-time. If the calculated minimal (or maximal) radius is the bigger than the related official radius it means that there exists a dark matter in this object. In that sense, the black holes are presenting the state of the matter at the minimal radius where we have the maximal radial mass (energy) density value. Further, the maximal possible radius of the matter is presenting the state with the minimal radial mass (energy) density value. Thus, the maximal and minimal radial mass (energy) density values are constants and conserved items. Now the question is: do motion of the Universe follows the RRDT?Full article
Article
ISSN: 2834-5479
DOI prefix: 10.31586/ujpr
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