Physical Sciences and Mathematics Commons^™

General Relativity, 8, David Peak

General Relativity

The Cosmic Microwave Background (CMB)

As previously noted, the universe is filled with microwave radiation. The frequency spectrum of this ubiquitous radiation follows a blackbody curve, as shown to the right. (http://map.gsfc.nasa.gov/media/ContentMedia/990015b.jpg) Note that photon energy (proportional to 1/wavelength) increases to the right. You might think the curve shown is the plot of a theoretical equation, but what is shown is actual measured data taken during the flight of the COBE (Cosmic Microwave Explorer) satellite/microwave observatory in 1990. The uncertainties in the measurements are about the thickness of the curve plotted. When compared with a theoretical blackbody curve the disagreement …

Inflation (Excel), David Peak

General Relativity

No abstract provided.

Structure Of Matter, 2, David Peak

Structure of Matter

Quantum electrodynamics

Quantum electrodynamics (QED) is the quantitatively best physical theory yet developed. Where it has been tested, it agrees with experiment to at least a few parts in 10¹¹! It is a theory of how charged particles and photons interact. It starts with electrons, for example, described by the Dirac Equation, interacting with photons described by a suitable electromagnetic potential energy.

Structure Of Matter, 3, David Peak

Structure of Matter

The particle zoo

Prior to the 1930s the fundamental structure of matter was believed to be extremely simple: there were electrons (each with mass about 0.5 MeV), e− , photons (no mass), γ , and protons (mass about 938 MeV), p⁺ . Starting in 1932 the world began to get a lot more complicated. First came Dirac’s positron ( e⁺ , with same mass as the electron), postulated in 1928 but mostly ignored until Anderson’s accidental discovery (see SM 1). Soon after, the neutron ( n ) was identified (mass about 940 MeV). In beta decay, the neutron …

Structure Of Matter, 5, David Peak

Structure of Matter

The quark-gluon plasma

At the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory on Long Island in New York (the only major research accelerator functioning in the US) and the Large Hadron Collider (LHC) at CERN in Switzerland, heavy atoms, stripped of most or all of their electrons, are collided with energies approaching 100-1000 GeV per nucleon. Traveling at nearly the speed of light, these heavy ions are Lorentz contracted into pancake shapes in the laboratory frame of reference and, consequently, have very large quark and gluon densities within the constituent protons and neutrons. The energy density in the …

Structure Of Matter, 8, David Peak

Structure of Matter

Neutrino mass and family mixing

Neutrinos are products of radioactive decay in many stellar fusion processes, primarily starting with the reaction p + p → ²He*→ ²H + e⁺ +ν_e . The nucleus ²He* is a highly unstable (that’s what the * represents) isotope of helium consisting of four primary u quarks and two primary d quarks. For years (since 1962 or so), various groups have been measuring the solar electron-neutrino flux, invariably observing it to be lower than theoretical predictions. Moreover, neutrinos are generated in the upper atmosphere, via collisions of cosmic ray particles …

Physics 3710 – Problem Set #4, David Peak

Problems

Physics 3710 – Problem Set #4 Relativistic kinematics, II

Physics 3710 – Problem Set #9, David Peak

Problems

Physics 3710 – Problem Set #9 Relativistic gravity, II

Physics 3710 – Problem Set #11, David Peak

Problems

Physics 3710 – Problem Set #11 QED Feynman diagrams

The solid arrows are electrons or positrons, the wavy lines are photons. Describe the “in” and “out” states shown below and describe what happens at each vertex. What is an overall name for each of the diagrams shown? (e.g., “electron-photon scattering”)

Physics 3710 – Problem Set #13, David Peak

Problems

Physics 3710 – Problem Set #13 Some weak interaction stuff

Questions 1-4 refer to the diagram at the right. In it, a particle p₁ absorbs a particle X and transforms into a particle p₂. Time increases vertically.

Experimental Validation Of The Generalized Harvey-Shack Surface Scatter Theory, Kevin T. Nattinger

Browse all Theses and Dissertations

The Generalized Harvey-Shack (GHS) surface scatter theory claims to predict the scatter from rough surfaces over a wide domain of validity but has not been widely implemented or tested. The focus of this research is to provide a documented implementation and experimental validation of the GHS theory for the prediction of the bidirectional reflectance distribution function (BRDF) from real rough surfaces. First, the GHS theory was developed for the MATLAB software and the details of its implementation and application to experimental comparison are discussed. Next, a BRDF measurement system was designed, built, and validated. The BRDF of the Spectralon reflectance …

Applied Temperament, Geoffrey D. Hershberger

Theses and Dissertations--Music

The following document was created in order to promote intonation consensus in ensembles and to better facilitate learning in educational settings. Non-keyboard instruments provide musicians an opportunity to make nearly infinitesimal adjustments to pitch while performing; this creates difficulties for students and challenges even the most seasoned professionals. Non-keyboard musicians struggle their whole lives to play in tune, and even when one knows exactly where they want to place a pitch, technical difficulties can foul any musician's performance. When performing solo, the musician must choose a tuning system that is suitable for the music being performed, and attempt to realize …

Two Stream Instability In Graphene, Mitchell Duffer

Williams Honors College, Honors Research Projects

Mitchell Duffer

Major: Physics

Project Sponsor: Ben Yu-Kuang Hu

Number of Project Credits: 2

Two Stream Instability in Graphene

We investigate the unstable modes of the two-stream instability in graphene to determine if they can occur. This instability occurs when a population of electrons streams past another inside graphene. We obtain the unstable modes by numerically determining the zeros of the non-equilibrium graphene dielectric function using MATLAB. The dielectric function used in this study, in contrast to previous studies, includes the effects of the particle-hole excitation continuum (PHEC) that normally quells the evolution of unstable plasmons. MATLAB’s built in zero …

A Comparison Of Online, Video Synchronous, And Traditional Learning Modes For An Introductory Undergraduate Physics Course, Emily K. Faulconer, John C. Griffith, Beverly Wood, Donna Roberts

Publications

While the equivalence between online and traditional classrooms has been well-researched, very little of this includes college-level introductory Physics. Only one study explored Physics at the whole-class level rather than specific course components such as a single lab or a homework platform. In this work, we compared the failure rate, grade distribution, and withdrawal rates in an introductory undergraduate Physics course across several learning modes including traditional face-to-face instruction, synchronous video instruction, and online classes. Statistically significant differences were found for student failure rates,grade distribution, and withdrawal rates but yielded small effect sizes. Post-hoc pair-wise test was run to determine …

Establishing A Quality Assurance Routine For Digital Imaging, Sulaiman Rana Al

Browse all Theses and Dissertations

In the clinical medical physics field, Quality Assurance (QA) is a fundamental topic to insure patient safety and effective treatment. In recent years, the imaging hardware for diagnostic x-rays has been shifting to fully digital detectors. However, the quality assurance tests for such detectors in the clinical setting is still under development. In the Medical Imaging Department of Kettering Hospital (Kettering, OH), the currently accepted method of performing QA on detectors is to use an extensive set of tests suggested by the manufacturer. This set of tests requires about 90 minutes, which is too long for daily use. The goal …

Examining The Response Of The Martian Atmosphere To Increases In Different Portions Of The Electromagnetic Spectrum During Solar Flares, Bradley R. Kumm

Master's Theses and Doctoral Dissertations

This report describes the methods used to examine how the Martian atmosphere responds to increases in different portions of the electromagnetic spectrum during solar flares. On March 24, 2015 the Mars Atmosphere and Volatile Evolution (MAVEN) mission satellite made measurements of the atmosphere and solar irradiance during a solar flare. These measurements were used by the Flare Irradiance Spectral Model (FISM) to generate solar flux values for 59 wavelength bins describing flare event. The solar flux values at different wavelength bins were scaled by different amounts and input into the Mars Global Ionosphere Thermosphere Model (M-GITM) to create 16 distinct …

Quantifying Effects Of Using Thermally Thin Fuel Approximations On Modelling Fire Propagation In Woody Fuels, David Blasen, Jesse Johnson, William Jolly, Russell Parsons

Graduate Student Theses, Dissertations, & Professional Papers

In this paper, we quantify the effects of the thermally thin fuel approximations commonly made in numerical models that eliminate temperature gradients within a heated object. This assumption is known to affect the modeled ignition and burn behavior, but there is little research on its impact, particularly in larger fuels or in numerical models including moisture and chemical decomposition of fuels.

We begin by comparing modeled to observed ignition times and burn rates. To constrain variability in the material properties of wood and focus on variability caused by fuels assumed to be thermally thin, we conduct experiments using thermogravimetric analysis …

The Encyclopedia Of Neutrosophic Researchers - Vol. 2, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

This is the second volume of the Encyclopedia of Neutrosophic Researchers, edited from materials offered by the authors who responded to my invitation. The introduction contains a short history of neutrosophics, together with links to the main papers and books. The authors who have published neutrosophic papers, books, or defended neutrosophic master theses or PhD dissertations and are not included in the two ENR volumes, are kindly invited to send their self-presentations or their CVs, a photo, and a list of neutrosophic publications to [email protected] and [email protected] to be part of a third volume.

Florentin Smarandache

Underwater Acoustic Signal Analysis Toolkit, Kirk Bienvenu Jr

LSU New Orleans Theses and Dissertations

This project started early in the summer of 2016 when it became evident there was a need for an effective and efficient signal analysis toolkit for the Littoral Acoustic Demonstration Center Gulf Ecological Monitoring and Modeling (LADC-GEMM) Research Consortium. LADC-GEMM collected underwater acoustic data in the northern Gulf of Mexico during the summer of 2015 using Environmental Acoustic Recording Systems (EARS) buoys. Much of the visualization of data was handled through short scripts and executed through terminal commands, each time requiring the data to be loaded into memory and parameters to be fed through arguments. The vision was to develop …

Muon-Neutrino Electron Elastic Scattering And A Search For The Muon-Neutrino Magnetic Moment In The Nova Near Detector, Biao Wang

Physics Theses and Dissertations

We use the NOvA near detector and the NuMI beam at Fermilab to study the neutrino-electron elastic scattering and the muon neutrino magnetic process beyond the Standard Model physics. The particle identifications of neutrino on electron elastic scattering are trained by using the multi-layer neural networks. This thesis provides a general discussion of this technique and shows a good agreement between data and MC for the neutrino-electron elastic weak scattering. By using 3.62e20 POT dataset in the NOvA near detector, we find 1.58e-9 Bohr magneton as the 90% C.L. upper limit. We also find a sensitivity of 8e-10 Bohr magneton …

Measurement Of Vector Boson Scattering And Constraints On Anomalous Quartic Couplings From Events √With Four Leptons And Two Jets In Proton–Proton Collisions At √ S = 13tev, The Cms Collaboration, M. M. Baarmand, Vallary Bhopatkar, S. Colafranceschi, M. Hohlmann, D. Noonan, T. Roy, F. Yumiceva

Aerospace, Physics, and Space Science Faculty Publications

A measurement of vector boson scattering and constraints on anomalous quartic gauge couplings from events with two Z bosons and two jets are presented. The analysis is based on a data sample of proton–proton collisions at 𝑠=13TeV collected with the CMS detector and corresponding to an integrated luminosity of 35.9fb−1. The search is performed in the fully leptonic final state ZZ→ℓℓℓ′ℓ′, where ℓ,ℓ′=e or μ. The electroweak production of two Z bosons in association with two jets is measured with an observed (expected) significance of 2.7 (1.6) standard deviations. A fiducial cross section for the electroweak production is measured …

Phys 211: Mechanics, Gravitation, And Waves, Ilya Kravchenko

Department of Physics and Astronomy: Syllabi

Syllabus for PHYS 211: Mechanics, Gravitation, and Waves syllabus for Fall 2017 semester.

College Of Science And Mathematics Newsletter, Fall 2017, College Of Science And Mathematics, Wright State University

College of Science and Mathematics Newsletters

This 6 page newsletter discusses various happenings within the College of Science and Mathematics. It begins with a letter from the dean, and continues on with news, events, alumni news, and other community news.

Phys 201: Modern Topics In Physics And Astronomy, Ken Bloom

Department of Physics and Astronomy: Syllabi

Syllabus for PHYS 201: Modern Topics in Physics and Astronomy syllabus for Fall 2017.

Nuclear Magnetic Resonance Studies Of Electrode And Electrolyte Materials For Li-Ion Batteries, Lisa Cirrincione

Dissertations, Theses, and Capstone Projects

In this thesis, Nuclear Magnetic Resonance (NMR) spectroscopic techniques are used to study lithium electrode and electrolyte materials for advanced rechargeable lithium ion batteries. Three projects are described in this thesis. The first involves ²³Na and ³⁷Al static and magic angle spinning NMR studies of NaAlH₄/C anode materials for advanced rechargeable batteries. The second project is a study of paramagnetic lithium transition-metal phosphate cathode materials for Li-ion batteries, where ⁷Li, and ³¹P single crystal NMR was used in order to obtain detailed information on the local electronic and magnetic environments. The third project investigates …

Foundations, 3, David Peak

Foundations

Our goal is to try to reconcile classical EM with the existence of photons. The electric and magnetic fields associated with EM radiation, propagating in the x -direction, obey the Maxwell wave equation: ∂²E/∂t² = c²(∂²E/∂x²).

Many-Particle Systems, 3, David Peak

Many Particles

Bare essentials of statistical mechanics

Atoms are examples of many-particle systems, but atoms are extraordinarily simpler than macroscopic systems consisting of 10²⁰-10³⁰ atoms. Despite their great size, many properties of macroscopic systems depend intimately on the microscopic behavior of their microscopic constituents. The proper quantum mechanical description of an N -particle system is a wavefunction that depends on 3N coordinates (3 ways of moving, in general, for every particle) and 4N quantum numbers (3 motional quantum numbers and 1 spin quantum number for every particle). (If the “particles” are molecules there might be additional quantum …

Many-Particle Systems, 1, David Peak

Many Particles

Wavefunctions for more than one particle: Different kinds of particles

Introductory examples of quantum mechanical wavefunction calculations involve a single particle moving about in a “magic” potential energy—e.g., a particle trapped inside a square well or an electron in a hydrogen atom. But, potential energy arises from interaction, so these situations must inevitably include more than one particle. Even the simplest atom—hydrogen— consists of two particles: the electron and the proton. So, how should the Schrödinger Equation be generalized to account for multiple particles?

Many-Particle Systems, 8, David Peak

Many Particles

The classical picture of how electrons migrate through a resistor driven by an applied potential difference draws an analogy with a kind of pinball machine. In a pinball machine, gravity accelerates the pinball down the table, but the ball’s progress is impeded by collisions with bumpers, as depicted to the right. (θ is the angle the table makes with the horizontal direction.) When averaged over many collisions the ball’s average equation of motion is ma = mg sinθ − mv/τ , where a and v are directed down the table, and τ is the average time between collisions. If the …

Problem Set #4, David Peak

Problems

Some 1D infinite well stuff