Graduate Students In Physics Research Articles

Outline on Selected Teaching Strategies to Improving the Knowledge of B.Sc., Students in Physics

This research is designed to study about the Effectiveness of selected teaching strategies in improving the knowledge of B.Sc., Students in Physics. Physics is the very important area in Science. The main purpose of the study is to identify the problems faced by the under graduate Physics students and how it can be rectified to generate in their field of Physics. In Physics, teaching methods are different principles and methods that are used to instruct students in a learning environment. The methods used by a lecturer will depend on the skills or information the lecturer would like to convey to their students. Some of the most common teaching methods are memorization, class participation, recitation, and demonstration. While these teaching methods are widely used, every instructor has a specific teaching method. Lecturers must be flexible in their subjects and often adjust their style of teaching to accommodate their students. Efficient teaching methods are essential tools that can help students to achieve success in the classroom. In college level each student has a different personality and learning abilities. There are several factors that a teacher must consider when choosing a teaching method for their students. Some determining factors for selecting a teaching method include the student’s interest and background knowledge, as well as their environment and learning abilities.

Physics graduate students join their peers in unionization efforts

Physics graduate students join their peers in unionization efforts

Graduate study in physical acoustics at the University of Mississippi

The University of Mississippi is a PhD granting institution with an R1 Carnegie designation placing it among schools with the highest level of research activity. The Department of Physics and Astronomy at the university has a diverse range of research opportunities which includes Physical Acoustics. Our acoustics program is affiliated with the National Center for Physical Acoustics (NCPA). NCPA is an 85,000 square foot standalone facility on the campus of the University of Mississippi solely dedicated to the physics and engineering applications of acoustics. It has research groups dedicated to ultrasound, infrasound, aeroacoustics, atmospheric propagation, porous media, and ocean acoustics. Graduate students in both physics and engineering are pursuing PhD and MS degrees at NCPA, and four faculty members from the physics department have their research laboratories in the facility. In addition to acoustics, our department provides a broad range of research opportunities in other subfields. We have two groups associated with recent Nobel Prizes in Gravitation and High Energy Physics and offer additional programs in Computational Physics and Atmospheric Physics. Our faculty are involved with national and international collaborations including the Laser Interferometer Gravitational Wave Observatory (LIGO), The European Center for Particle Physics (CERN) and Fermilab.

Construction and Application of Automatic Attendance Prediction System for Classroom Education Teaching Based on Random Matrix Theory

Random matrix theory, as a theoretical tool for statistical processing of complex systems and high-dimensional data, has been more and more combined with big data technology and applied to automatic attendance prediction analysis of classroom education. Firstly, the basic definition of the random matrix is introduced. Secondly, the single ring theorem of the random matrix is introduced. Based on this, the random matrix model of data is established. However, few undergraduate or graduate students in physics have been exposed to this theory. By introducing the basic concept of random matrix theory, this paper analyzes the necessity and feasibility of introducing random matrix theory into automatic attendance prediction teaching in classroom education. As a biometrics technology, random matrix theory technology has been widely used in various fields of the identity verification system, and classroom attendance system is an important field of random matrix theory technology application. The traditional random matrix theory class attendance has the problem of slow recognition speed and low accuracy. With the popularity of deep learning, the random matrix theory based on deep learning has gradually replaced the traditional random matrix theory. In this paper, the SSD target detection algorithm, NB algorithm, and RF algorithm based on deep learning are used to improve and optimize the traditional random matrix theory class attendance system, which effectively improves the efficiency and accuracy of random matrix theory attendance. Then, aiming at the low recall rate and recognition rate of random matrix theory in low-pixel images, we try to apply the random matrix theory of single image resolution reconstruction method to face detection and random matrix theory and give a calculation method to deal with outliers and noise.

Didactic laser speckle experiments with a lensless camera

Laser speckles are granular patterns created through the interference of coherent light scattered by a rough surface. Besides comprising an appealing optical phenomenon, the speckle patterns enable applications in physical and biochemical measurements. This paper proposes didactic far-field (objective) speckle experiments using a visible laser source and a lensless webcam for implementation in optics labs or at home. Firstly, a ceramic mug works as the scattering surface to investigate the effect of the target-observation plane distance on the average size of light granules. Secondly, the speckle pattern deviations produced by the liquid inside the recipient are analysed to measure mass and temperature changes. Finally, the mug is replaced with a leaf to evaluate its biological activity based on the scattered light. Image processing tools carry out the quantification of speckle parameters like average size and correlation coefficient, achieving a good agreement between theory and practical results. The proposed far-field speckle experiments explore topics related to optics, instrumentation, and image computing straightforwardly, developing the desired skills for undergraduate and graduate students of physics and engineering courses.

A toy model for relativistic neutrino masses

We propose a toy model to study Dirac charged leptons and their associated antineutrinos in the presence of a homogeneous magnetic field within the framework of relativistic quantum mechanics. The discussion is kept concrete by reducing the space dimensions to 2, considering ‘spinless antineutrinos’ in 2 + 1 space-time dimensions. Solutions to specific problems in particle physics are often hindered by the technical complexities encountered in -dimensions. In such cases, it is convenient to have a lower space dimensional model at ones disposal that captures some physical features while reducing technical difficulties to a minimum. The content of this article is suitable for graduate students in theoretical and experimental particle physics.

Application of the Helfrich elasticity theory to the morphology of red blood cells

In this work, we present in detail, in an accessible manner for undergraduate and graduate physics students, the model of spontaneous curvature, due to Helfrich, that quantitatively explains why the red blood cells in their natural state adopt a biconcave shape. The main hypothesis is that the equilibrium cell shape satisfies the principle of minimum free energy. Therefore, in the model, an expression for the membrane free energy is postulated based on the Helfrich theory. In that approximation, the membrane is modelled as a two-dimensional surface and the energy is written as a function of the surface principal curvatures and three parameters, including the spontaneous curvature, c0, which is associated with the chemical composition of the membrane. The negative values for c0 induce invaginations in the cell membrane. The model predicts the discocyte-spherocyte transition for the red blood cell. In the article, the concepts involved in the theory are developed in detail, and an algorithm that allows obtaining the contour of the cell is presented in detail as supplementary material.

The basis of the semiclassical description of electron transport in solids

The theoretical account of electron transport in crystalline solids is often taught to graduate students through a semiclassical equation, which is a classical kinetic equation amended with elements of quantum physics in a non-systematic way. This blending of classical and quantal elements accounts for many experimental features of electron transport, save for a few ones observed over short distances. For students acquainted with solid-state quantum mechanics, it is preferable to derive the semiclassical equation from quantum dynamics so as to pinpoint the shortcomings and approximations underlying the semiclassical picture of transport. This paper explores the pathway leading from quantum dynamics to semiclassical kinetics within a simplified model not exceeding the proficiencies of a graduate student in physics or electronic engineering. In this model an electron moves in a crystal under the joint influences of the periodic crystal potential, an external electrostatic field and a set of lattice imperfections haphazardly distributed in the crystal volume. The first influence is treated exactly by means of standard energy-band theory and the other two are handled perturbatively. Following a procedure already tested in free-space issues, we replace Schrödinger’s wave function in position space with a Wigner function defined in the phase (position–pseudomomentum) space of semiclassical kinetics. The dynamical equation on the Wigner function is worked out and approximated so as to retrieve the semiclassical equation. The errors incurred in making use of the latter are assessed quantitatively. It is explained how a time-irreversible evolution equation—governing a phase-space occupancy—arises from reversible Schrödinger dynamics—governing a complex-valued probability amplitude. Besides clarifying the foundation of the semiclassical picture of electron transport and providing an explicit quantum-coherence correction to that picture, this paper may help students in general physics to better grasp, in a concrete issue, the interplay between classical and quantum concepts.

Isolation and connectedness among Black and Latinx physics graduate students

Physics graduate students who are exposed to political demonstrations that threaten people of color describe that supportive action from their program makes a difference to their persistence.

Primer on ILC physics and SiD software tools

We first outline the standard model of particle physics, particle production and decay, and the expected signal and background at a Higgs factory like the international linear collider (ILC). We then introduce high-energy colliders and collider detectors and briefly detail the ILC and the silicon detector (SiD), one of the two detectors proposed for the ILC. Next, we review the available software tools for ILC event generation, SiD detector simulation, and event reconstruction. Finally, we suggest open avenues in research for detector optimization and physics analysis. The pedagogical level is suitable for advanced undergraduate and beginning graduate students in physics and research scientists in related fields.

The Pauli and Lévy-Leblond equations, and the spin current density

We review the literature on the Pauli equation and its current density, discussing the progression from the original phenomenological version of Pauli to its derivation by Lévy-Leblond from a linearization of the Schrödinger equation. It was established conclusively by Lévy-Leblond’s work that the spin of a spin-1/2 particle such as an electron is non-relativistic in nature, contrary to what was often stated following Dirac’s derivation of a relativistic wave equation, and his subsequent demonstration that Pauli’s spin interaction term appeared in the non-relativistic limit. In this limit, the Gordon decomposition of the associated probability current density was found to contain a spin-dependent term. Such a term does not follow, however, from the usual derivation of the current density from the Pauli equation, although various physically motivated but otherwise ad hoc explanations were put forward to account for it. We comment on the only exception to these of which we are aware implying the spin term in the current was in fact non-relativistic in nature. However, the earlier work of Lévy-Leblond had already shown, with no additional assumptions, that this term was a prominent feature of the current density derived from his equation. Hence, just as with the spin itself, the spin current was non-relativistic, claims to the contrary notwithstanding. We present a somewhat simplified derivation of the Lévy-Leblond equation and its current density, commenting on possibilities for experimental work that might indicate measurable consequences of the spin term in the current density. The presentation is at a level of quantum mechanics, electromagnetic theory, and mathematical methods typical of courses taken by first-year graduate students in physics, assuming some familiarity with Pauli spin matrices and the Dirac equation. Calculations are presented in detail, making the material suitable for use by teachers as supplementary problems for assignments, and development of theoretical concepts peculiar to the Pauli equation and its probability current density.

Approximate analytical description for the nonlinear -symmetric coupled-mode equations

In this paper, we present an approximate analytical description of the solutions dynamics of nonlinear -symmetric coupled-mode equations which can be used to realize the nonlinear -symmetric optical configuration. By the multiple-scale analysis, we construct the asymptotic solutions of the coupled-mode equations. In the -symmetry unbroken region, there is a good agreement between the asymptotic solutions and exact numerical solutions, and the higher-order asymptotic series can yield a higher accuracy. However, in the -symmetry broken region, the asymptotic solutions become invalid quickly as z increases. Instead, we neglect one linear coupling term and obtain the approximate analytical solutions which, to some extent, describe the dynamics in the -symmetry broken region when z ≫ 1. This paper may be helpful for undergraduate and graduate students in physics to understand the nonlinear dynamics of -symmetric systems.

Teaching Practice about Parallel Scientific Computing for Graduate Students Majored in Physics

With the rapid developments of computer hardware and software, nowadays parallel computing is playing more and more important roles in the scientific research in physics related fields. The broad use of supercomputers and computer clusters makes it possible to solve much more efficiently various scientific problems by computations and simulations. Therefore, to gain basic knowledge and programming skills of parallel computing is very necessary for junior graduate students majored in physics, while the teaching of these knowledge and skills has been lacking in the traditional course of computational physics. Here, we present a teaching practice of parallel computing for junior graduate students in physics, which has been shown to be successful by the homework presentation of the students

Nonlinear Maxwell equations and the Poynting theorem

Considering that classical electrodynamics is essentially a covariant theory, we propose a simple heuristic approach to nonlinear Maxwell equations where certain scalar fields are coupled to the electromagnetic (EM) field. This leads us to introduce a new (nonlinear) version of the Poynting theorem. This model seems to have solutions in which coupled scalar fields and EM waves propagate. This work could provide students with a first introduction to the basics of nonlinear electrodynamics within the framework of a new research problem. The content of this article is suitable for advanced graduate students in theoretical particle physics.

Complete set of commuting observables for a two-site Hubbard model

The aim of this paper is to present an exact solution of the Hubbard model in a simplified case. Considering the simplest problem of a two-site entity, a solution of the model is obtained by using a suitable complete set of commuting observables. Owing to this approach, we show that some features of the physics of insulating and metallic systems may be understood within a simple unified picture. Furthermore, we are confident that this purely quantum mechanical approach turns out to be of particular interest for a general reader and undergraduate or graduate physics students.

Graduate study in physical acoustics at the University of Mississippi

The University of Mississippi is a Ph.D. granting institution with an R1 Carnegie designation placing it among schools with the highest level of research activity. The Department of Physics and Astronomy at Ole Miss has a diverse range of research opportunities, including two groups associated with recent Nobel Prizes. Along with programs in Computational Physics, High Energy Physics, Atmospheric Physics and Gravitation, the department is affiliated with the National Center for Physical Acoustics (NCPA). NCPA is an 85 000 square foot standalone facility on the campus of the University of Mississippi dedicated to the physics and engineering applications of acoustics. It has research groups dedicated to ultrasound, infrasound, aeroacoustics, atmospheric propagation, porous media, and ocean acoustics. Graduate students in physics and engineering are pursuing Ph.D. and M.S. degrees at NCPA, and four faculty members from the Physics department have their research laboratories in the facility. In addition to NCPA, the Physics department has affiliations with the Laser Interferometer Gravitational Wave Observatory (LIGO), The European Center for Particle Physics (CERN), Fermilab and Belle II.

Quantum Geometry I: Basics of Loop Quantum Gravity

General Relativity describes gravity in geometrical terms. This sug-gests that quantising such theory is the same as quantising geometry.The subject can therefore be called quantum geometry and one maythink that mathematicians are responsible of this subject. Unfortunatelymost mathematicians are not aware of this beautiful area of study. Herewe give a basic introduction to what quantum geometry means to a com-munity working in a theory known as loop quantum gravity. It is directedtowards graduate or upper students of physics and mathematics. We doit so from a point of view of a mathematician.

Canonical methods in classical and quantum gravity: An invitation to canonical LQG

Loop Quantum Gravity (LQG) is a candidate quantum theory of gravity still under construction. LQG was originally conceived as a background independent canonical quantization of Einstein’s general relativity theory. This contribution provides some physical motivations and an overview of some mathematical tools employed in canonical Loop Quantum Gravity. First, Hamiltonian classical methods are reviewed from a geometric perspective. Canonical Dirac quantization of general gauge systems is sketched next. The Hamiltonian formultation of gravity in geometric ADM and connection-triad variables is then presented to finally lay down the canonical loop quantization program. The presentation is geared toward advanced undergradute or graduate students in physics and/or non-specialists curious about LQG.

Chuckrow’s theory of the prenatal origin of music

In 1965, the second author, a graduate student in physics at New York University, drafted a paper entitled “Music: A synthesis of prenatal stimuli,” in which he proposed that structural elements of music such as rhythm and melody are analogs of fetal stimuli. In the 1980s, the first author independently published a similar theory. Both authors considered fetal perception of internal body sounds, correlations between those sounds and maternal states, the ability of the fetus to hear and remember sound patterns, biological and behavioral correlates of emotions shared by mother and fetus, transfer of hormones across the placenta, and effects of maternal psychopathology on infant behavior. Both argued that consideration of fetal consciousness is unnecessary because unconscious learning can influence later conscious behaviors and experiences. Chuckrow uniquely proposed that meter and polymeter, perceived as combinations of approximately isochronous pulses with one pulse in the foreground, might derive from the combined sound of maternal and fetal heartbeats as perceived by the fetus. We evaluate these theories in the context of more recent approaches to the origin of music. A systematic consideration of prenatal influences can parsimoniously explain communicative, emotional and structural aspects of music. Music may be a by-product of adaptations such as prenatal hearing and motherese that promoted infant survival in ancient hunter-gatherer settings.

Fluid dynamics in porous media with Sailfish

In this work we show the application of Sailfish to the study of fluid dynamics in porous media. Sailfish is an open-source software based on the lattice-Boltzmann method. This application of computational fluid dynamics is of particular interest to the oil and gas industry and the subject could be a starting point for an undergraduate or graduate student in physics or engineering. We built artificial samples of porous media with different porosities and used Sailfish to simulate the fluid flow through them in order to calculate their permeability and tortuosity. We also present a simple way to obtain the specific superficial area of porous media using Python libraries. To contextualise these concepts, we analyse the applicability of the Kozeny–Carman equation, which is a well-known permeability–porosity relation, to our artificial samples.