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Full-Text Articles in Physics

Elmer Fem-Dakota: A Unified Open-Source Computational Framework For Electromagnetics And Data Analytics, Anjali Sandip Aug 2020

Elmer Fem-Dakota: A Unified Open-Source Computational Framework For Electromagnetics And Data Analytics, Anjali Sandip

Mechanical Engineering Faculty Publications

Open-source electromagnetic design software, Elmer FEM, was interfaced with data analytics toolkit, Dakota. Furthermore, the coupled software was validated against a benchmark test. The interface developed provides a unified open-source computational framework for electromagnetics and data analytics. Its key features include uncertainty quantification, surrogate modelling and parameter studies. This framework enables a richer understanding of model predictions to better design electric machines in a time sensitive manner.


Design, Monitoring And Management Approaches For The Root-Zone In Microgravity, Scott B. Jones Jul 2020

Design, Monitoring And Management Approaches For The Root-Zone In Microgravity, Scott B. Jones

Funded Research Records

No abstract provided.


Noncontextuality Inequalities From Antidistinguishability, Matthew S. Leifer, Cristhiano Duarte Jun 2020

Noncontextuality Inequalities From Antidistinguishability, Matthew S. Leifer, Cristhiano Duarte

Mathematics, Physics, and Computer Science Faculty Articles and Research

Noncontextuality inequalities are usually derived from the distinguishability properties of quantum states, i.e., their orthogonality. Here, we show that antidistinguishability can also be used to derive noncontextuality inequalities. The Yu-Oh 13-ray noncontextuality inequality can be rederived and generalized as an instance of our antidistinguishability method. For some sets of states, the antidistinguishability method gives tighter bounds on noncontextual models than just considering orthogonality, and the Hadamard states provide an example of this. We also derive noncontextuality inequalities based on mutually unbiased bases and symmetric informationally complete positive operator-valued measures. Antidistinguishability based inequalities were initially discovered as overlap bounds for ...


Acoustic Versus Electromagnetic Field Theory: Scalar, Vector, Spinor Representations And The Emergence Of Acoustic Spin, Lucas Burns, Konstantin Y. Bliokh, Franco Nori, Justin Dressel May 2020

Acoustic Versus Electromagnetic Field Theory: Scalar, Vector, Spinor Representations And The Emergence Of Acoustic Spin, Lucas Burns, Konstantin Y. Bliokh, Franco Nori, Justin Dressel

Mathematics, Physics, and Computer Science Faculty Articles and Research

We construct a novel Lagrangian representation of acoustic field theory that describes the local vector properties of longitudinal (curl-free) acoustic fields. In particular, this approach accounts for the recently-discovered nonzero spin angular momentum density in inhomogeneous sound fields in fluids or gases. The traditional acoustic Lagrangian representation with a scalar potential is unable to describe such vector properties of acoustic fields adequately, which are however observable via local radiation forces and torques on small probe particles. By introducing a displacement vector potential analogous to the electromagnetic vector potential, we derive the appropriate canonical momentum and spin densities as conserved Noether ...


A Note On The Fine Structure Constant, Bilal Khan, Irshadullah Khan Apr 2020

A Note On The Fine Structure Constant, Bilal Khan, Irshadullah Khan

CSE Technical reports

We derive the numerical value of the fine structure constant in purely number-theoretic terms, under the assumption that in a system of charges between two parallel conducting plates, the Casimir energy and the mutual Coulomb interaction energy agree.


A Note On The Fine Structure Constant, Bilal Khan, Irshadullah Khan Apr 2020

A Note On The Fine Structure Constant, Bilal Khan, Irshadullah Khan

Sociology Department, Faculty Publications

We derive the numerical value of the fine structure constant in purely number-theoretic terms, under the assumption that in a system of charges between two parallel conducting plates, the Casimir energy and the mutual Coulomb interaction energy agree.


A Note On The Fine Structure Constant, Bilal Khan, Irshadullah Khan Apr 2020

A Note On The Fine Structure Constant, Bilal Khan, Irshadullah Khan

Sociology Department, Faculty Publications

We derive the numerical value of the fine structure constant $\alpha$ in purely number-theoretic terms, under the assumption that in a system of charges between two parallel conducting plates, the Casimir energy and the mutual Coulomb interaction energy agree.


Measurements Of Radio Pulse Reception With Stations Of The Ara Experiment Based On The Spicecore Pulser Data Set, Jesse Osborn, Ilya Kravchenko Dr. Apr 2020

Measurements Of Radio Pulse Reception With Stations Of The Ara Experiment Based On The Spicecore Pulser Data Set, Jesse Osborn, Ilya Kravchenko Dr.

UCARE Research Products

The Askaryan Radio Array Experiment located near the South Pole works to pinpoint specific instances of neutrinos from outside the solar system interacting with nucleons inside the Antarctic ice. Neutrinos are a subatomic particle that has nearly no mass and a net neutral charge. As they are, neutrinos tend not to interact with anything as they travel through space which means they can provide us with information about events occurring far from Earth that might not be easily attained through other methods. Neutrinos are known to be emitted from a myriad of sources, including the Sun, the interaction between cosmic ...


An Analysis Of The Debate Over Creation, Evolution, And The Timeline Of The Universe At An Ecumenical Christian University, Mason Pohlman Apr 2020

An Analysis Of The Debate Over Creation, Evolution, And The Timeline Of The Universe At An Ecumenical Christian University, Mason Pohlman

Honors Theses

Throughout a significant portion of history and within modern culture, the fields of science and religion appear to be competing for the same holds in a person’s belief system. Universities are where academics and the sciences are the prevailing held truth, while in churches, the Bible reigns as supreme authority. However, in a Christian academic setting, the predominate school of thought in belief systems might turn into a little more of a melting pot. By analyzing gathered personal data (via surveys and interviews), one can begin to piece together the predominate thoughts on the apparent conflict between religion and ...


Magnetic Forces In The Absence Of A Classical Magnetic Field, Ismael L. Paiva, Yakir Aharonov, Jeff Tollaksen, Mordecai Waegell Apr 2020

Magnetic Forces In The Absence Of A Classical Magnetic Field, Ismael L. Paiva, Yakir Aharonov, Jeff Tollaksen, Mordecai Waegell

Mathematics, Physics, and Computer Science Faculty Articles and Research

It is shown that, in some cases, the effect of discrete distributions of flux lines in quantum mechanics can be associated with the effect of continuous distributions of magnetic fields with special symmetries. In particular, flux lines with an arbitrary value of magnetic flux can be used to create energetic barriers, which can be used to confine quantum systems in specially designed configurations. This generalizes a previous work where such energy barriers arose from flux lines with half-integer fluxons. Furthermore, it is shown how the Landau levels can be obtained from a two-dimensional grid of flux lines. These results suggest ...


Designing Writing Intensive Upper Division Laboratories In Physics, Sara Callori Feb 2020

Designing Writing Intensive Upper Division Laboratories In Physics, Sara Callori

Q2S Enhancing Pedagogy

California State University San Bernardino is currently transitioning from quarters to semesters, starting in Fall 2020. As part of this transition, the Department of Physics has transformed its curriculum to better suit the needs of its students. One major facet of this redesign has been the creation of two writing intensive, upper division laboratory courses. From a practical standpoint, under the revamped general education program, we are able to incorporate upper division writing into the major. More importantly, there are many benefits where having a writing-intensive major course aligns with program goals and professional organization recommendations. This includes designing activities ...


Overview Of Trends In Indian Optics Research (2008 – 2018), Mallikarjun Kappi, Biradar B S Feb 2020

Overview Of Trends In Indian Optics Research (2008 – 2018), Mallikarjun Kappi, Biradar B S

Library Philosophy and Practice (e-journal)

The present study deals with the assessment of Indian optics research output as reflected in Web of Science (WOS) database for the period 2008 to 2018 for identifying the research output in the field of optics literature. It also provides a comparative evaluation and performance of different types of scientometric indicators, such as number of publications, number of citations and collaboration from India. The Indian optics research has increased exponentially over the last decade.


Performing Near Field Acoustic Holography Scans For The Purpose Of Finding The Acoustic Impedance Of A Violin, Zamara Tomko Jan 2020

Performing Near Field Acoustic Holography Scans For The Purpose Of Finding The Acoustic Impedance Of A Violin, Zamara Tomko

Student Research, Papers, and Creative Works

This project aimed to measure the acoustic impedance of the violin so that the violin can be better understood from an acoustic standpoint. Near field acoustic holography scans are to be conducted at the open A string resonance of the violin (440 Hz). Pressure microphones along the back plate of the violin allow pressure and particle velocity to be measured, and with that, the acoustic impedance to be calculated and mapped in 1 cm x 1cm increments. This work presents a guide for this procedure. The set-up method and materials used are detailed and the analysis and computations of values ...


Detection Of Decoupled Surface And Bulk States In Epitaxial Orthorhombic Sriro3 Thin Films, Prescott E. Evans, Takashi Komesu, Le Zhang, Ding-Fu Shao, Andrew J. Yost, Shiv Kumar, Eike F. Schwier, Kenya Shimada, Evgeny Y. Tsymbal, Xia Hong, P. A. Dowben Jan 2020

Detection Of Decoupled Surface And Bulk States In Epitaxial Orthorhombic Sriro3 Thin Films, Prescott E. Evans, Takashi Komesu, Le Zhang, Ding-Fu Shao, Andrew J. Yost, Shiv Kumar, Eike F. Schwier, Kenya Shimada, Evgeny Y. Tsymbal, Xia Hong, P. A. Dowben

Peter Dowben Publications

We report the experimental evidence of evolving lattice distortion in high quality epitaxial orthorhombic SrIrO3(001) thin films fully strained on (001) SrTiO3 substrates. Angle-resolved X-ray photoemission spectroscopy studies show that the surface layer of 5 nm SrIrO3 films is Sr–O terminated, and subsequent layers recover the semimetallic state, with the band structure consistent with an orthorhombic SrIrO3(001) having the lattice constant of the substrate. While there is no band folding in the experimental band structure, additional super-periodicity is evident in low energy electron diffraction measurements, suggesting the emergence of a transition layer with crystal symmetry evolving from ...


Rod-Shape Theranostic Nanoparticles Facilitate Antiretroviral Drug Biodistribution And Activity In Human Immunodeficiency Virus Susceptible Cells And Tissues, Bhavesh D. Kevadiya, Brendan Ottemann, Insiya Z. Mukadam, Laura Castellanos, Kristen Sikora, James R. Hilaire, Jatin Machhi, Jonathan Herskovitz, Dhruvkumar Soni, Mahmudul Hasan, Wenting Zhang, Anandakumar Sarella, Jered Garrison, Joellyn Mcmillan, Benson Edagwa, R. Lee Mosley, Richard W. Vachet, Howard E. Gendelman Jan 2020

Rod-Shape Theranostic Nanoparticles Facilitate Antiretroviral Drug Biodistribution And Activity In Human Immunodeficiency Virus Susceptible Cells And Tissues, Bhavesh D. Kevadiya, Brendan Ottemann, Insiya Z. Mukadam, Laura Castellanos, Kristen Sikora, James R. Hilaire, Jatin Machhi, Jonathan Herskovitz, Dhruvkumar Soni, Mahmudul Hasan, Wenting Zhang, Anandakumar Sarella, Jered Garrison, Joellyn Mcmillan, Benson Edagwa, R. Lee Mosley, Richard W. Vachet, Howard E. Gendelman

Faculty Publications from Nebraska Center for Materials and Nanoscience

Human immunodeficiency virus theranostics facilitates the development of long acting (LA) antiretroviral drugs (ARVs) by defining drug-particle cell depots. Optimal drug formulations are made possible based on precise particle composition, structure, shape and size. Through the creation of rod-shaped particles of defined sizes reflective of native LA drugs, theranostic probes can be deployed to measure particle-cell and tissue biodistribution, antiretroviral activities and drug retention.

Methods: Herein, we created multimodal rilpivirine (RPV) 177lutetium labeled bismuth sulfide nanorods (177LuBSNRs) then evaluated their structure, morphology, configuration, chemical composition, biological responses and adverse reactions. Particle biodistribution was analyzed by single photon emission ...


Analysis Of Magnetization Directions Of Lunar Swirls, Lillie Cole Jan 2020

Analysis Of Magnetization Directions Of Lunar Swirls, Lillie Cole

Lewis Honors College Capstone Collection

Lunar Swirls are high albedo markings on the Moon that exist in the regions of some crustal magnetic anomalies. The precise mechanism responsible for the swirl features is unknown but a prevailing theory is solar wind standoff, where the magnetic field from subsurface magnetized sources protects the lunar surface from solar wind ions, leading to their lesser maturation and brighter appearance. If this theory is correct, the magnetic field of the anomalies should heavily influence the appearance of the swirl. To better understand the cause of swirls, the magnetization direction of the source creating the field is analyzed. This study ...


Svat4: A Computer Program For Visualization And Analysis Of Crystal Structures, Xingzhong Li Jan 2020

Svat4: A Computer Program For Visualization And Analysis Of Crystal Structures, Xingzhong Li

Faculty Publications from Nebraska Center for Materials and Nanoscience

SVAT4 is a computer program for interactive visualization of three-dimensional crystal structures, including chemical bonds and magnetic moments. A wide range of functions, e.g. revealing atomic layers and polyhedral clusters, are available for further structural analysis. Atomic sizes, colors, appearance, view directions and view modes (orthographic or perspective views) are adjustable. Customized work for the visualization and analysis can be saved and then reloaded. SVAT4 provides a template to simplify the process of preparation of a new data file. SVAT4 can generate high-quality images for publication and animations for presentations. The usability of SVAT4 is broadened by a software ...


Chiral Magnetism And High-Temperature Skyrmions In B20-Ordered Co-Si, Balamurugan Balasubramanian, Priyanka Manchanda, Rabindra Pahari, Zhen Chen, Wenyong Zhang, Shah R. Valloppilly, Xingzhong Li, Anandakumar Sarella, Lanping Yue, Ahsan Ullah, Pratibha Dev, David A. Muller, Ralph Skomski, George C. Hadjipanayis, David J. Sellmyer Jan 2020

Chiral Magnetism And High-Temperature Skyrmions In B20-Ordered Co-Si, Balamurugan Balasubramanian, Priyanka Manchanda, Rabindra Pahari, Zhen Chen, Wenyong Zhang, Shah R. Valloppilly, Xingzhong Li, Anandakumar Sarella, Lanping Yue, Ahsan Ullah, Pratibha Dev, David A. Muller, Ralph Skomski, George C. Hadjipanayis, David J. Sellmyer

Faculty Publications from Nebraska Center for Materials and Nanoscience

Magnets with chiral crystal structures and helical spin structures have recently attracted much attention as potential spin-electronics materials, but their relatively low magnetic-ordering temperatures are a disadvantage. While cobalt has long been recognized as an element that promotes high-temperature magnetic ordering, most Co-rich alloys are achiral and exhibit collinear rather than helimagnetic order. Crystallographically, the B20-ordered compound CoSi is an exception due to its chiral structure, but it does not exhibit any kind of magnetic order. Here, we use nonequilibrium processing to produce B20-ordered Co1+xSi1−x with a maximum Co solubility of x = 0.043. Above ...


The Effect Of Size Upon Haptic Shape Discrimination, Jessica Dukes Jan 2020

The Effect Of Size Upon Haptic Shape Discrimination, Jessica Dukes

Mahurin Honors College Capstone Experience/Thesis Projects

Object shape perception is fundamentally important for daily life. It has been suggested (e.g., Gibson, 1962) that the visual and haptic modalities are equivalent with regards to the ability to perceive shape. Norman et al. (2012) showed that visual and haptic shape discrimination accuracies are indeed comparable. Craddock and Lawson (2009) found that haptic shape discrimination performance was adversely affected by a size change. However, this result was obtained for man-made objects (i.e., bathtubs and benches). The purpose of the current investigation was to determine whether size changes also reduce haptic shape discrimination accuracy for naturally-shaped objects. On ...


Characterising Hot Stellar Systems With Confidence, Souradeep Chattopadhyay, Ranjan Maitra Jan 2020

Characterising Hot Stellar Systems With Confidence, Souradeep Chattopadhyay, Ranjan Maitra

Statistics Publications

Hot stellar systems (HSS) are a collection of stars bound together by gravitational attraction. These systems hold clues to many mysteries of outer space so understanding their origin, evolution and physical properties is important but remains a huge challenge. We used multivariate t-mixtures model-based clustering to analyze 13456 hot stellar systems from Misgeld & Hilker (2011) that included 12763 candidate globular clusters and found eight homogeneous groups using the Bayesian Information Criterion (BIC). A nonparametric bootstrap procedure was used to estimate the confidence of each of our clustering assignments. The eight obtained groups can be characterized in terms of the correlation ...


Optimizing Measurement Strengths For Qubit Quasiprobabilities Behind Out-Of-Time-Ordered Correlators, Razieh Mohseninia, José Raúl González Alonso, Justin Dressel Dec 2019

Optimizing Measurement Strengths For Qubit Quasiprobabilities Behind Out-Of-Time-Ordered Correlators, Razieh Mohseninia, José Raúl González Alonso, Justin Dressel

Mathematics, Physics, and Computer Science Faculty Articles and Research

Out-of-time-ordered correlators (OTOCs) have been proposed as a tool to witness quantum information scrambling in many-body system dynamics. These correlators can be understood as averages over nonclassical multitime quasiprobability distributions (QPDs). These QPDs have more information and their nonclassical features witness quantum information scrambling in a more nuanced way. However, their high dimensionality and nonclassicality make QPDs challenging to measure experimentally. We focus on the topical case of a many-qubit system and show how to obtain such a QPD in the laboratory using circuits with three and four sequential measurements. Averaging distinct values over the same measured distribution reveals either ...


A Harmless Wireless Quantum Alternative To Cell Phones Based On Quantum Noise, Florentin Smarandache, Robert Neil Boyd, Victor Christianto Sep 2019

A Harmless Wireless Quantum Alternative To Cell Phones Based On Quantum Noise, Florentin Smarandache, Robert Neil Boyd, Victor Christianto

Mathematics and Statistics Faculty and Staff Publications

In the meantime we know that 4G and 5G technologies cause many harms to human health. Therefore, here we submit a harmless wireless quantum alternative to cell phones. It is our hope that this alternative


Benchmarks Of Nonclassicality For Qubit Arrays, Mordecai Waegell, Justin Dressel Aug 2019

Benchmarks Of Nonclassicality For Qubit Arrays, Mordecai Waegell, Justin Dressel

Mathematics, Physics, and Computer Science Faculty Articles and Research

We present a set of practical benchmarks for N-qubit arrays that economically test the fidelity of achieving multi-qubit nonclassicality. The benchmarks are measurable correlators similar to two-qubit Bell correlators, and are derived from a particular set of geometric structures from the N-qubit Pauli group. These structures prove the Greenberger–Horne–Zeilinger (GHZ) theorem, while the derived correlators witness genuine N-partite entanglement and establish a tight lower bound on the fidelity of particular stabilizer state preparations. The correlators need only MN + 1 distinct measurement settings, as opposed to the 22N − 1 settings that would normally be required ...


Luminosity-Luminosity Correlations In Flux-Limited Multiwavelength Data, J. Singal, V. Petrosian, J. Haider, S. Malik May 2019

Luminosity-Luminosity Correlations In Flux-Limited Multiwavelength Data, J. Singal, V. Petrosian, J. Haider, S. Malik

Physics Faculty Publications

We explore the general question of correlations among different waveband luminosities in a flux-limited multiband observational data set. Such correlations, often observed for astronomical sources, may be either intrinsic or induced by the redshift evolution of the luminosities and the data truncation due to the flux limits. We first address this question analytically. We then use simulated flux-limited data with three different known intrinsic luminosity correlations and prescribed luminosity functions and evolution similar to the ones expected for quasars. We explore how the intrinsic nature of luminosity correlations can be deduced, including exploring the efficacy of partial correlation analysis with ...


Analyzing The Mindsets And Behaviors Of Introductory Physics Students Through The Lens Of Intellectual Humility, Meagan Sundstrom May 2019

Analyzing The Mindsets And Behaviors Of Introductory Physics Students Through The Lens Of Intellectual Humility, Meagan Sundstrom

University Scholar Projects

Students often enter the physics classroom with intuitive conceptions drawn from real life experiences or former coursework, and may be hesitant or reluctant to re-evaluate these mindsets in favor of formally instructed knowledge. The goal of introductory physics courses is not only to teach and expose students to new content, but also to cultivate students’ ability to reason through and derive content knowledge through personal inquiry. This scientific process necessitates one’s abilities to be open-minded in terms of hearing evidence that contradicts his or her personal opinion, to be willing to discard any original misconceptions in the face of ...


Analyzing The Mindsets And Behaviors Of Introductory Physics Students Through The Lens Of Intellectual Humility, Meagan Sundstrom May 2019

Analyzing The Mindsets And Behaviors Of Introductory Physics Students Through The Lens Of Intellectual Humility, Meagan Sundstrom

Honors Scholar Theses

Students often enter the physics classroom with intuitive conceptions drawn from real life experiences or former coursework, and may be hesitant or reluctant to re-evaluate these mindsets in favor of formally instructed knowledge. The goal of introductory physics courses is not only to teach and expose students to new content, but also to cultivate students’ ability to reason through and derive content knowledge through personal inquiry. This scientific process necessitates one’s abilities to be open-minded in terms of hearing evidence that contradicts his or her personal opinion, to be willing to discard any original misconceptions in the face of ...


The Population Densities Of Argon Metastable Levels, Nada Khogeer, Chelsy Gonzalez, Milka Nikolic Apr 2019

The Population Densities Of Argon Metastable Levels, Nada Khogeer, Chelsy Gonzalez, Milka Nikolic

Physics and Astronomy

In this experiment, we used the optical emission spectroscopy (OES) method to obtain the main properties of low temperature Argon plasma. The experiment was sustained in powers and pressures that ranges from 30-100 W and 15-100 mTorr. We used numerical methods for the Argon kinetic model to calculate metastable levels and resonant states for the first excited states in low temperature Argon plasma. By finding the ratio of two spectral lines and finding another ratio from a different upper energy level that goes down to the same two lower energy levels, we can construct a system of two nonlinear equations ...


Sympathetic Physics: The Keely Motor And The Laws Of Thermodynamics In Nineteenth-Century Culture, Robert Macdougall Apr 2019

Sympathetic Physics: The Keely Motor And The Laws Of Thermodynamics In Nineteenth-Century Culture, Robert Macdougall

History Publications

In Philadelphia in the 1870s, John Worrell Keely announced the invention of a fantastic new motor that could, he promised, drive locomotives, power factories, and even defy gravity without fuel or heat. The Keely Motor became the most notorious perpetual motion scheme of the nineteenth century, attracting believers and investors for nearly thirty years. This article explores the “work” the motor performed for Keely, his supporters, and his critics—not physical work, but financial, cultural, and psychological. To investors, the Keely Motor represented a dream of riches without effort. To Keely’s critics, the motor offered an opportunity to defend ...


An Investigation Of The Detection Capability Of Pulsed Wave Duplex Doppler Of Low Grade Stenosis Using Ultrasound Contrast Agent Microbubbles – An In-Vitro Study, Jacinta Browne, Deirdre King, Andrew Fagan, Deepa Chari, Carmel Moran Apr 2019

An Investigation Of The Detection Capability Of Pulsed Wave Duplex Doppler Of Low Grade Stenosis Using Ultrasound Contrast Agent Microbubbles – An In-Vitro Study, Jacinta Browne, Deirdre King, Andrew Fagan, Deepa Chari, Carmel Moran

Articles

Objective: The objective of the study was to investigate whether clinically used ultrasonic contrast agents improved the accuracy of spectral Doppler ultrasound in the detection of low grade (< 50%) renal artery stenosis. Low grade stenoses in the renal artery are notoriously difficult to reliably detect using Doppler ultrasound due to difficulties such as overlying fat and bowel gas.

Methods: A range of anatomically-realistic renal artery phantoms with varying low degrees of stenosis (0, 30 and 50%) were constructed and peak velocity data was measured from within the pre-stenotic and mid-stenotic regions in each phantom, for both unenhanced and contrast-enhanced spectral Doppler data acquisitions. The effect of a 20mm overlying fat layer on the ultrasound beam distortion and phase aberration, and hence on the measured peak velocity data, was also investigated ...


Semiclassically Modeling Hydrogen At Rydberg States Immersed In Electromagnetic Fields, Jaron Williams Apr 2019

Semiclassically Modeling Hydrogen At Rydberg States Immersed In Electromagnetic Fields, Jaron Williams

Mathematics Senior Capstone Papers

Originally, closed-orbit theory was developed in order to analyze oscillations in the near ionization threshold (Rydberg) densities of states for atoms in strong external electric and magnetic fields. Oscillations in the density of states were ascribed to classical orbits that began and ended near the atom. In essence, observed outgoing waves following the classical path return and interfere with original outgoing waves, giving rise to oscillations. Elastic scattering from one closed orbit to another gives additional oscillations in the cross-section. This study examines how quantum theory can be properly used in combination with classical orbit theory in order to study ...