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General Relativity, 3, David Peak

General Relativity

Gravity as geometry: part II

Even in a region of space-time that is so small that tidal effects cannot be detected, gravity still seems to produce curvature. The argument for this point of view starts with the recognition that, for mechanical systems, it is impossible to distinguish a frame of reference with a uniform gravitational field from a uniformly accelerating frame that has no gravity. Thus, for example, in a (small) rocket ship with no windows it is not possible to determine whether the weight one reads standing on a scale at the tail of the rocket is due to …

Background, 1, David Peak

Background

This course deals with the structure of matter at its extreme length scales: cosmological on the large end (on the order of 1026 m), sub-nuclear on the small (less than 10-19 m). It also deals with the now firmly established realization that the organization of matter on these two phenomenally different scales is actually intimately connected. This course is about science in its most alive and vibrant state: what we think we know about the big and small of the universe changes virtually daily. Satellite observatories and ground-based particle accelerators make what was formerly “common knowledge” obsolete at a rapid …

History Graph, David Peak

Background

History graph image.

General Relativity, 1, David Peak

General Relativity

In special relativity, events occur in the arena of space-time which may be coordinatized differently by different observers, but which is otherwise immutable. Adding gravity to relativity provides an amazing result: space-time becomes “organic,” taking its form from the matter and energy it contains. This is Einstein’s general theory of relativity and it has the capacity to tell us about the past and future of the universe. Embedded in the history book of the cosmos are several chapters on the origins of matter. As a result, relativity + gravity unites the structures of matter on the largest and smallest scales.

General Relativity, 4, David Peak

General Relativity

Orbital motion of small test masses

The starting point for analyzing free fall trajectories in the (2-space, 1-time) Schwarzschild spacetime is Equation (3) from GR 3:

General Relativity, 6, David Peak

General Relativity

Modern cosmography

The “normal” matter in the universe—i.e., stuff made of protons, neutrons, and electrons— consists, approximately, of lumps floating in a dilute fog. The lumps are galaxies, clusters of 10⁷ to 10¹¹ stars bound together by gravity. In the currently observable universe, it is estimated that there are roughly 10¹¹ galaxies. The dilute fog is primarily neutral atomic hydrogen gas with some helium-4 mixed in (making up a total of 98% or more of the fog); there are also very small fractions of ²H (deuterium), ³He , and ⁷Li . The ratio …

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.

Edutainment: Weaving Your Passion Into The Process Of Stem Education, William Robertson

Selected Works Temporary Series

This presentation will focus on the use of live action and video instruction as a method of content dissemination and to motivate students in learning in science, technology, engineering and mathematics (STEM) education. Specifically, this area, dubbed “edutainment”, will chronicle different interactions with students, teachers and community members that utilized live action to video as methods of capturing relevant content in student-centered contexts. The fundamental idea is to infuse one's passion into your methods of teaching, and to inspire others to use their gifts in their education, and thereby connect them to their dreams and aspirations.

Edutainment: Weaving Your Passion Into The Process Of Stem Education, William Robertson

Departmental Papers (TE)

This presentation will focus on the use of live action and video instruction as a method of content dissemination and to motivate students in learning in science, technology, engineering and mathematics (STEM) education.  Specifically, this area, dubbed “edutainment”, will chronicle different interactions with students, teachers and community members that utilized live action to video as methods of capturing relevant content in student-centered contexts. The fundamental idea is to infuse one's passion into your methods of teaching, and to inspire others to use their gifts in their education, and thereby connect them to their dreams and aspirations.

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 …

Mississippians In Physics: Perspectives And Practice In A Search For Physics Excellence, Paul D. Rogers

Electronic Theses and Dissertations

This mixed-method study represents a broad evaluation of the physics views of Mississippi physics students and physicists, along with an analysis of graduate school data, in a search for answers which might improve physics education in Mississippi. Descriptive statistics were calculated using data from eight graduate degree programs (from Fall 2003 through Full Summer 2012) at the University of Mississippi. This was done to find the percent of graduate degrees in each degree program which were awarded to in-state residents. It was found that of the eight University of Mississippi graduate degree programs in the study, two programs awarded a …

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 …

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 …

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

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 …

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 …

Search For The Pair Production Of Third-Generation Squarks With Two-Body Decays To A Bottom Or Charm Quark And A Neutralino In Proton–Proton Collisions At √S=13 Tev, S. Chatrchyan, Ekaterina Avdeeva, Kenneth Bloom, S. Bose, Jamila Butt, Daniel R. Claes, Aaron Dominguez, M. Eads, R. Gonzalez Suarez, P. Jindal, J. Keller, D. Knowlton, Ilya Kravchenko, Jose Lazo-Flores, Helena Malbouisson, Sudhir Malik, F. Meier, Gregory Snow

Gregory Snow Publications

Results are presented from a search for the pair production of third-generation squarks in proton–proton collision events with two-body decays to bottom or charm quarks and a neutralino, which produces a significant imbalance in the transverse momentum. The search is performed using a sample of proton–proton collision data at √s=13 TeV recorded by the CMS experiment at the LHC, corresponding to an integrated luminosity of 35.9fb⁻¹. No statistically significant excess of events is observed beyond the expected contribution from standard model processes. Exclusion limits are set in the context of simplified models of bottom or top squark pair …

Acoustic Nonreciprocity In Coriolis Mean Flow Systems, Masoud Naghdi, Farhad Farzbod

Faculty and Student Publications (Open Access)

No abstract provided.

Pseudorapidity Distributions Of Charged Hadrons In Proton-Lead Collisions At S N N = 5.02 $$ \Sqrt{S_{\Mathrm{Nn}}}=5.02 $$ And 8.16 Tev, Cms Collaboration, J. G. Acosta, S. Oliveros

Faculty and Student Publications (Open Access)

No abstract provided.

Search For Resonant And Nonresonant Higgs Boson Pair Production In The B B ¯ ℓνℓν $$ \Mathrm{B}\Overline{\Mathrm{B}}\Mathit{\Ell \Nu \Ell \Nu } $$ Final State In Proton-Proton Collisions At S = 13 $$ \Sqrt{S}=13 $$ Tev, Cms Collaboration, J. G. Acosta, S. Oliveros

Faculty and Student Publications (Open Access)

No abstract provided.

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 …