Advances in Fundamental Physics II

A special issue of Foundations (ISSN 2673-9321). This special issue belongs to the section "Physical Sciences".

Deadline for manuscript submissions: closed (31 August 2023) | Viewed by 24912

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Department of Physics, Auburn University, Auburn, AL 36849-5319, USA
Interests: atomic and molecular physics; astrophysics; plasma physics
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Special Issue Information

Dear Colleagues,

This Special Issue continues celebrating the opening of a new section of the journal Foundation: Physical Sciences - after the great success of the first Special Issue of the same title. We invite theoretical and experimental studies related to all areas of fundamental physics. We welcome reviews and regular research papers without imposing any restrictions on the length of the paper. We also welcome short communications. These are expected to contain a preliminary presentation of interesting, potentially important ideas. 

Prof. Dr. Eugene Oks
Guest Editor

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Keywords

  • classical mechanics
  • quantum mechanics
  • atomic, molecular, and optical physics
  • physics of plasmas and gases (including plasma spectroscopy)
  • astronomy and astrophysics (including cosmology)
  • condensed matter physics
  • nuclear physics
  • physics of elementary particles and fields
  • interdisciplinary physics

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Published Papers (13 papers)

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19 pages, 2029 KiB  
Article
Lévy Walks as a Universal Mechanism of Turbulence Nonlocality
by Alexander B. Kukushkin and Andrei A. Kulichenko
Foundations 2023, 3(3), 602-620; https://doi.org/10.3390/foundations3030036 - 20 Sep 2023
Viewed by 1118
Abstract
The nonlocality (superdiffusion) of turbulence is expressed in the empiric Richardson t3 scaling law for the mean square of the mutual separation of a pair of particles in a fluid or gaseous medium. The development of the theory of nonlocality of various [...] Read more.
The nonlocality (superdiffusion) of turbulence is expressed in the empiric Richardson t3 scaling law for the mean square of the mutual separation of a pair of particles in a fluid or gaseous medium. The development of the theory of nonlocality of various processes in physics and other sciences based on the concept of Lévy flights resulted in Shlesinger and colleagues’ about the possibility of describing the nonlocality of turbulence using a linear integro-differential equation with a slowly falling kernel. The approach developed by us made it possible to establish the closeness of the superdiffusion parameter of plasma density fluctuations moving across a strong magnetic field in a tokamak to the Richardson law. In this paper, we show the possibility of a universal description of the characteristics of nonlocality of transfer in a stochastic medium (including turbulence of gases and fluids) using the Biberman–Holstein approach to examine the transfer of excitation of a medium by photons, generalized in order to take into account the finiteness of the velocity of excitation carriers. This approach enables us to propose a scaling that generalizes Richardson’s t3 scaling law to the combined regime of Lévy flights and Lévy walks in fluids and gases. Full article
(This article belongs to the Special Issue Advances in Fundamental Physics II)
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10 pages, 382 KiB  
Communication
Emergent Gravity Simulations for Schwarzschild–de Sitter Scenarios
by Arno Keppens
Foundations 2023, 3(2), 231-240; https://doi.org/10.3390/foundations3020019 - 14 May 2023
Viewed by 1457
Abstract
Building on previous work that considered gravity to emerge from the collective behaviour of discrete, pre-geometric spacetime constituents, this work identifies these constituents with gravitons and rewrites their effective gravity-inducing interaction in terms of local variables for Schwarzschild–de Sitter scenarios. This formulation enables [...] Read more.
Building on previous work that considered gravity to emerge from the collective behaviour of discrete, pre-geometric spacetime constituents, this work identifies these constituents with gravitons and rewrites their effective gravity-inducing interaction in terms of local variables for Schwarzschild–de Sitter scenarios. This formulation enables graviton-level simulations of entire emergent gravitational systems. A first simulation scenario confirms that the effective graviton interaction induces the emergence of spacetime curvature upon the insertion of a graviton condensate into a flat spacetime background. A second simulation scenario demonstrates that free fall can be considered to be fine-tuned towards a geodesic trajectory, for which the graviton flux, as experienced by a test mass, disappears. Full article
(This article belongs to the Special Issue Advances in Fundamental Physics II)
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21 pages, 334 KiB  
Article
Different Mass Definitions and Their Pluses and Minuses Related to Gravity
by Espen Gaarder Haug
Foundations 2023, 3(2), 199-219; https://doi.org/10.3390/foundations3020017 - 18 Apr 2023
Cited by 4 | Viewed by 3322
Abstract
The discussion of what matter and mass are has been going on for more than 2500 years. Much has been discovered about mass in various areas, such as relativity theory and modern quantum mechanics. Still, quantum mechanics has not been unified with gravity. [...] Read more.
The discussion of what matter and mass are has been going on for more than 2500 years. Much has been discovered about mass in various areas, such as relativity theory and modern quantum mechanics. Still, quantum mechanics has not been unified with gravity. This indicates that there is perhaps something essential not understood about mass in relation to gravity. In relation to gravity, several new mass definitions have been suggested in recent years. We will provide here an overview of a series of potential mass definitions and how some of them appear likely preferable for a potential improved understanding of gravity at a quantum level. This also has implications for practical things such as getting gravity predictions with minimal uncertainty. Full article
(This article belongs to the Special Issue Advances in Fundamental Physics II)
7 pages, 986 KiB  
Communication
Zero-Energy Bound States of Neutron–Neutron or Neutron–Muon Systems
by Eugene Oks
Foundations 2023, 3(1), 65-71; https://doi.org/10.3390/foundations3010007 - 6 Feb 2023
Viewed by 1378
Abstract
There exists the following paradigm: for interaction potentials U(r) that are negative and go to zero as r goes to infinity, bound states may exist only for the negative total energy E. For E > 0 and for E = 0, [...] Read more.
There exists the following paradigm: for interaction potentials U(r) that are negative and go to zero as r goes to infinity, bound states may exist only for the negative total energy E. For E > 0 and for E = 0, bound states are considered to be impossible, both in classical and quantum mechanics. In the present paper we break this paradigm. Namely, we demonstrate the existence of bound states of E = 0 in neutron–neutron systems and in neutron–muon systems, specifically when the magnetic moments of the two particles in the pair are parallel to each other. As particular examples, we calculate the root-mean-square size of the bound states of these systems for the values of the lowest admissible values of the angular momentum, and show that it exceeds the neutron radius by an order of magnitude. We also estimate the average kinetic energy and demonstrate that it is nonrelativistic. The corresponding bound states of E = 0 may be called “neutronium” (for the neutron–neutron systems) and “neutron–muonic atoms” (for the neutron–muon systems). We also point out that this physical system possesses higher-than-geometric (i.e., algebraic) symmetry, leading to the approximate conservation of the square of the angular momentum, despite the geometric symmetry being axial. We use this fact for facilitating analytical and numerical calculations. Full article
(This article belongs to the Special Issue Advances in Fundamental Physics II)
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15 pages, 653 KiB  
Article
Physics of the Earth’s Glacial Cycle
by Boris M. Smirnov
Foundations 2022, 2(4), 1114-1128; https://doi.org/10.3390/foundations2040073 - 7 Dec 2022
Cited by 2 | Viewed by 1932
Abstract
The evolution of the atmospheric temperature in the past, resulted from the EPICA project (European Project for Ice Coring in Antarctica) for the analysis of air bubbles in ice deposits near three weather stations in Antarctica, includes several glacial cycles. According to these [...] Read more.
The evolution of the atmospheric temperature in the past, resulted from the EPICA project (European Project for Ice Coring in Antarctica) for the analysis of air bubbles in ice deposits near three weather stations in Antarctica, includes several glacial cycles. According to these studies, the glacial cycle consists of a slow cooling of the Earth’s surface at a rate of about 104C per year for almost the entire time of a single cycle (about 100 thousand years) and of a fast process of heating the planet, similar to a thermal explosion. The observed cooling of the planet follows from the imbalance of energy fluxes absorbed by the Earth and going into its surrounding space, and this imbalance is four orders of magnitude less than the accuracy of determination of the fluxes themselves. The inconsistency of the popular Milankovich theory is shown, according to which glacial cycles in the evolution of the Earth’s thermal state are associated with changes in the Earth’s orbit relative to the Sun. In considering the glacial cycle as the transition between the warm (contemporary) and cold thermal states of the Earth with a difference in their temperatures of 12 C according to measurements, we construct the energetic balance for each of Earth’s states. The fast transition between the Earth’s cold and warm states results from the change of the Earth’s albedo due to the different volcano activity in these states. There is the feedback between the aggregate state of water covering the Earth’s surface and volcanic eruptions, which become intense when ice covers approximately 40% of the Earth’s surface. Dust measurements in ice deposits within the framework of the EPICA project confirms roughly a heightened volcano eruption during the cold phase of the glacial cycle. Numerical parameters of processes related to the glacial cycle are analyzed. Full article
(This article belongs to the Special Issue Advances in Fundamental Physics II)
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18 pages, 845 KiB  
Article
Elemental Laser-Plasma Analysis of Pointed Gourd Leaves for Diabetes Management
by Tejmani Kumar, Prashant K. Rai, Abhishek K. Rai, Nilesh K. Rai, Awadhesh K. Rai, Christian G. Parigger, Geeta Watal and Suman Yadav
Foundations 2022, 2(4), 981-998; https://doi.org/10.3390/foundations2040066 - 26 Oct 2022
Cited by 4 | Viewed by 1925
Abstract
This interdisciplinary work communicates the identification and quantification of elements responsible for the bioactive potency of leaves from pointed gourd, trichosanthes dioica, using laser-induced breakdown spectroscopy (LIBS). Calibration-free LIBS determines the presence of various trace and major elements, their concentrations, and ratios [...] Read more.
This interdisciplinary work communicates the identification and quantification of elements responsible for the bioactive potency of leaves from pointed gourd, trichosanthes dioica, using laser-induced breakdown spectroscopy (LIBS). Calibration-free LIBS determines the presence of various trace and major elements, their concentrations, and ratios in which they are present in the leaves. The presence of specific elemental ratios of magnesium/sodium and magnesium/potassium could be promising for managing diabetes mellitus. Variable doses of aqueous extract from trichosanthes dioica leaves are administered for determination of the most effective one. Based on encouraging results, the extract could be harvested to serve as anti-diabetic medication for diabetes and associated symptoms. Full article
(This article belongs to the Special Issue Advances in Fundamental Physics II)
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15 pages, 7947 KiB  
Article
Hydroxyl Spectroscopy of Laboratory Air Laser-Ignition
by Christian G. Parigger
Foundations 2022, 2(4), 934-948; https://doi.org/10.3390/foundations2040064 - 18 Oct 2022
Cited by 1 | Viewed by 1853
Abstract
This work investigates spatial and temporal distributions of hydroxyl, OH, in laser-plasma in laboratory air at standard ambient temperature and pressure. Of interest are determination of temperature and density of OH and establishment of a correlation of molecular OH emission spectra with shadow [...] Read more.
This work investigates spatial and temporal distributions of hydroxyl, OH, in laser-plasma in laboratory air at standard ambient temperature and pressure. Of interest are determination of temperature and density of OH and establishment of a correlation of molecular OH emission spectra with shadow graphs for time delays of 50 to 100 μs, analogous to previous work on shadow graph and emission spectroscopy correlation for cyanide, CN, in gas mixtures and for time delays of the order of 1 μs. Wavelength- and sensitivity-corrected spatiotemporal data analysis focuses on temperature inferences using molecular OH emission spectroscopy. Near-IR radiation from a Q-switched laser device initiates optical breakdown in laboratory air. The laser device provides 6 ns, up to 850 milli Joule, pulses at a wavelength of 1064 nm, and focal irradiance in the range of 1 to 10 terawatt per centimeter-squared. Frequency doubled beams are utilized for capturing shadow graphs for visualization of the breakdown kernel at time delays in the range of 0.1 to 100 μs. OH emission spectra of the laser plasma, spatially resolved along the slit dimension, are recorded in the wavelength range of 298 nm to 321 nm, and with gate widths adjusted to 10 μs for the intensified charge-coupled device that is mounted at the exit plane of a 0.64 m Czerny-Turner configuration spectrometer. Diatomic OH signals occur due to recombination of the plasma and are clearly distinguishable for time delays larger than 50 μs, but are masked by spectra of N2 early in the plasma decay. Full article
(This article belongs to the Special Issue Advances in Fundamental Physics II)
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6 pages, 222 KiB  
Communication
A Possible Explanation of the Proton Radius Puzzle Based on the Second Flavor of Muonic Hydrogen Atoms
by Eugene Oks
Foundations 2022, 2(4), 912-917; https://doi.org/10.3390/foundations2040062 - 13 Oct 2022
Cited by 5 | Viewed by 1543 | Correction
Abstract
The proton radius puzzle is one of the most fundamental challenges of modern physics. Before the year 2010, the proton charge radius rp was determined by the spectroscopic method, relying on the electron energy levels in hydrogen atoms, and by the elastic [...] Read more.
The proton radius puzzle is one of the most fundamental challenges of modern physics. Before the year 2010, the proton charge radius rp was determined by the spectroscopic method, relying on the electron energy levels in hydrogen atoms, and by the elastic scattering of electrons on protons. In 2010, and then in 2013, two research teams determined rp from the experiment on muonic hydrogen atoms and they claimed rp to be by about 4% smaller than it was found from the experiments with electronic hydrogen atoms. Since then, several research groups performed corresponding experiments with electronic hydrogen atoms and obtained contradictory results: some of them claimed that they found the same value of rp as from the muonic hydrogen experiments, while others reconfirmed the larger value of rp. The conclusion of the latest papers (including reviews) is that the puzzle is not resolved yet. In the present paper, we bring to the attention of the research community, dealing with the proton radius puzzle, the contributing factor never taken into account in any previous calculations. This factor has to do with the hydrogen atoms of the second flavor, whose existence is confirmed in four different types of atomic experiments. We present a relatively simple model illustrating the role of this factor. We showed that disregarding the effect of even a relatively small admixture of the second flavor of muonic hydrogen atoms to the experimental gas of muonic hydrogen atoms could produce the erroneous result that the proton charge radius is by about 4% smaller than its actual value, so that the larger out of the two disputed values of the proton charge radius could be, in fact, correct. Full article
(This article belongs to the Special Issue Advances in Fundamental Physics II)
14 pages, 493 KiB  
Article
Isotopic Shift in Hg-Isotopes within Brückner versus Relativistic Energy Density Functional
by Jeet Amrit Pattnaik, Joshua T. Majekodunmi, Mrutunjaya Bhuyan and Suresh Kumar Patra
Foundations 2022, 2(4), 898-911; https://doi.org/10.3390/foundations2040061 - 12 Oct 2022
Cited by 1 | Viewed by 1764
Abstract
The present study is focused on revealing a characteristic kink of the neutron shell closure N = 126 across the Hg-isotopic chain within the relativistic mean-field (RMF) approach with the IOPB-I, DD-ME2, DD-PC1 and NL3 parameter sets. The RMF densities are converted to [...] Read more.
The present study is focused on revealing a characteristic kink of the neutron shell closure N = 126 across the Hg-isotopic chain within the relativistic mean-field (RMF) approach with the IOPB-I, DD-ME2, DD-PC1 and NL3 parameter sets. The RMF densities are converted to their spherical equivalence via the Wood–Saxon approximation and used as input within the parametrization procedure of the coherent density fluctuation model (CDFM). The nuclear matter symmetry energy is calculated using the Brückner energy density functional, and its surface, as well as volume components, are evaluated within Danielwicz’s liquid drop prescription. In addition, a comparison between Brückner and relativistic energy density functionals using the NL3 parameter set is shown as a representative case. The binding energy, charge distribution radius and symmetry energy are used as indicators of the isotopic shift in both ground and isomeric states. We have found the presence of a kink at the shell/sub-shell closure at N = 126 for neutron-rich 206Hg. The formation of the kink is traceable to the early filling of the 1i11/2 orbitals rather than 2g9/2, due to the large spin-orbit splitting. As such, the link between the occupational probability and the magicity of nuclei over the Hg-isotopic chain is established. Full article
(This article belongs to the Special Issue Advances in Fundamental Physics II)
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1 pages, 162 KiB  
Correction
Correction: Oks, E. A Possible Explanation of the Proton Radius Puzzle Based on the Second Flavor of Muonic Hydrogen Atoms. Foundations 2022, 2, 912–917
by Eugene Oks
Foundations 2023, 3(3), 560; https://doi.org/10.3390/foundations3030032 - 4 Sep 2023
Viewed by 660
Abstract
There was an error/misprint in the original publication [...] Full article
(This article belongs to the Special Issue Advances in Fundamental Physics II)
12 pages, 1324 KiB  
Brief Report
Deriving an Electric Wave Equation from Weber’s Electrodynamics
by Qingsong Li and Simon Maher
Foundations 2023, 3(2), 323-334; https://doi.org/10.3390/foundations3020024 - 7 Jun 2023
Viewed by 2189
Abstract
Weber’s electrodynamics presents an alternative theory to the widely accepted Maxwell–Lorentz electromagnetism. It is founded on the concept of direct action between particles, and has recently gained some momentum through theoretical and experimental advancements. However, a major criticism remains: the lack of a [...] Read more.
Weber’s electrodynamics presents an alternative theory to the widely accepted Maxwell–Lorentz electromagnetism. It is founded on the concept of direct action between particles, and has recently gained some momentum through theoretical and experimental advancements. However, a major criticism remains: the lack of a comprehensive electromagnetic wave equation for free space. Our motivation in this research article is to address this criticism, in some measure, by deriving an electric wave equation from Weber’s electrodynamics based on the axiom of vacuum polarization. Although this assumption has limited experimental evidence and its validity remains a topic of debate among researchers, it has been shown to be useful in the calculation of various quantum mechanical phenomena. Based on this concept, and beginning with Weber’s force, we derive an expression which resembles the familiar electric field wave equation derived from Maxwell’s equations. Full article
(This article belongs to the Special Issue Advances in Fundamental Physics II)
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9 pages, 599 KiB  
Brief Report
Methylidyne Cavity Ring-Down Spectroscopy in a Microwave Plasma Discharge
by László Nemes and Christian G. Parigger
Foundations 2023, 3(1), 16-24; https://doi.org/10.3390/foundations3010002 - 5 Jan 2023
Viewed by 1786
Abstract
This work communicates cavity ring-down spectroscopy (CRDS) of methylidyne (CH) in a chemiluminescent plasma that is produced in a microwave cavity. Of interest are the rotational lines of the 0-0 vibrational transition for the A–X band and the 1-0 vibrational transition for the [...] Read more.
This work communicates cavity ring-down spectroscopy (CRDS) of methylidyne (CH) in a chemiluminescent plasma that is produced in a microwave cavity. Of interest are the rotational lines of the 0-0 vibrational transition for the A–X band and the 1-0 vibrational transition for the B–X band. The reported investigations originate from research on the CH radical in 1996, which constituted the first case of applying CRDS to the CH radical. The report also includes a recent analysis that shows excellent agreement of the measured and computed data, and it communicates CH line strength data. The CH radical is an important diatomic molecule in hydrocarbon combustion diagnosis and the analysis of stellar plasma emissions, to name just two examples of analytical plasma chemistry. Full article
(This article belongs to the Special Issue Advances in Fundamental Physics II)
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15 pages, 1381 KiB  
Technical Note
Diatomic Line Strengths for Fitting Selected Molecular Transitions of AlO, C2, CN, OH, N2+, NO, and TiO, Spectra
by Christian G. Parigger
Foundations 2023, 3(1), 1-15; https://doi.org/10.3390/foundations3010001 - 1 Jan 2023
Cited by 4 | Viewed by 2747
Abstract
This work communicates line-strength data and associated scripts for the computation and spectroscopic fitting of selected transitions of diatomic molecules. The scripts for data analysis are designed for inclusion in various software packages or program languages. Selected results demonstrate the applicability of the [...] Read more.
This work communicates line-strength data and associated scripts for the computation and spectroscopic fitting of selected transitions of diatomic molecules. The scripts for data analysis are designed for inclusion in various software packages or program languages. Selected results demonstrate the applicability of the program for data analysis in laser-induced optical breakdown spectroscopy primarily at the University of Tennessee Space Institute, Center for Laser Applications. Representative spectra are calculated and referenced to measured data records. Comparisons of experiment data with predictions from other tabulated diatomic molecular databases confirm the accuracy of the communicated line-strength data. Full article
(This article belongs to the Special Issue Advances in Fundamental Physics II)
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