Physics Commons^™

Optimisation Of Photosensitive Recording Materials For Broadband Holographic Optical Elements, Michael Murray

Doctoral

The introduction of broadband (white) LED outdoor lighting has led to significant energy savings. However, this has come at the cost of increased light pollution which has negative impacts both on ecological systems and human health. This light pollution is largely the result of the lack of control measures for the directionality of the light emitted by outdoor LED lighting. The lack of directionality also results in higher energy consumption in order to compensate for the light scattered to the atmosphere and sufficiently illuminate the target area. In this thesis holographic optical elements (HOEs) are proposed as a complementary technology …

The Trouble Of Energy: Theoretical Foundations Of Loop Quantum Gravity, Hallie Gift

Senior Honors Theses

While general relativity and quantum mechanics have proved to be successful theories with elegant explanations of special cases, an underlying theory is needed to harmonize their copious discrepancies. Popular theories to reconcile the two are broadly termed “quantum gravity,” which refers to theories that introduce a discretized component of gravity either by directly suggesting gravitational quanta or attempting to discretize spacetime geometry. Loop quantum gravity falls under the latter category; it respects the background independence intrinsic to general relativity while attempting to provide an explanation of underlying quantum behavior via Planck-scale-level geometrical discretization. This thesis aims to provide a primer …

Volume 17, Christian O’Neill, Kyara Greene, Savva Sidorov, Laura Bisaillon, Luke Clemmer, Hannah Gordon, Kitt Benson, Taylor Blount, Rachel Danzitz, Nicholas Duellman, Chase Gionis, Hima Fernando, Seth Franzyshen, Onyx Gonzalez, Bryan Lin, Samantha Start, Ysabel Wells, Maggie Duncan

Incite: The Journal of Undergraduate Scholarship

Introduction Dr. Amorette Barber, Director, Office of Student Research

From the Editor Dr. Hannah Dudley-Shotwell

Cover Artist’s Statement Maggie Duncan

On Mentoring Dr. Yulia Uryadova

Ukrainian Resistance in the Face of Russification: Nestor Makhno and Anarchism

by Christian O’Neill

Life Vest by Kyara Greene

Isolation and 16S rRNA Identification of Bacteria from Fire Department Connection Pipe by Savva Sidorov

The Effectiveness of Planned Exercise in Reducing ADHD Symptoms in Children by Laura Bisaillon & Luke Clemmer

Linguistic Analysis on Confidence and Communication Strategies with Disparities Between Sign Fluency and Hearing Impairment by Hannah Gordon

Freedmen in Indian Territory by Kitt …

Membrane Organization Of Rheb And Rhoa: Roles In Function And Allosteric Druggability, Chase M. Hutchins

Dissertations and Theses (Open Access)

Small GTPases of the Ras superfamily are membrane-bound molecular switches that regulate nearly all major cellular processes, and their dysregulation drives cancers, neurological disorders, and metabolic diseases. While anchored to cellular membranes, the catalytic domains of small GTPases undergo orientation dynamics, adopting distinct configurations that can occlude or expose effector-binding surfaces and modulate signaling output. These dynamics have been characterized in the Ras oncoproteins, but whether they extend across the superfamily and influence allosteric druggability has remained unknown.

In this dissertation, I address these questions through Rheb and RhoA, two small GTPases with complementary differences in subfamily lineage, membrane localization, …

Structural Relaxation In Glass-Forming Liquids At Extreme Pressure: Photon-Correlation Spectroscopy And Constrained Thermodynamic Surface Modeling, Kevin Wayne Lyon

Graduate Theses and Dissertations

Structural relaxation in glass-forming liquids is strongly dependent on both temperature and pressure, yet direct measurement of structural α-relaxation under multi-gigapascal compression has remained experimentally challenging. This work extends depolarized photon correlation spectroscopy (DPCS) to pressures approaching 5 GPa in a diamond anvil cell, representing the highest-pressure implementation of this technique and enabling direct measurement of the structural α-relaxation in a pure liquid at extreme compression. This capability provides access to dynamical regimes previously unexplored by photon correlation spectroscopy and establishes a platform for probing glassy dynamics at high pressure. To describe these measurements, a constrained relaxation-time surface framework is …

From Vibration To Visualization: Building An Real-Time Audio Visualization System For Learning And Exploration Using Pyqt5, Aidan Roach

The Transdisciplinary STEAM+ Journal

This paper presents the design, development, and analysis of my real-time audio visualization system created entirely in Python using PyQt5, called WaveCatcher. The system captures live audio input from a microphone and provides simultaneous visual feedback through multiple signal representations: including a time-domain waveform, a frequency-domain FFT spectrum, a scrolling spectrogram, harmonic peak visualization, dynamic range, amplitude envelope, spectral centroid, and spectral bandwidth. These features offer insight not just into the raw structure of sound, but into how humans perceive its qualities–like timbre! This terminology may seem intimidating—it certainly was when I first began learning it—but I’ll explain all of …

Form And Fusion: The Art And Science Of Ceramics And Glass, Juniper J. Bauroth-Sherman, Kaleigh Evans

Interdivisional Studies Presentations

The first Ceramics & Art class (IDS-110-F: ST: Ceramics) has completed an immersive, interdisciplinary exploration of stained glass and we’re excited to showcase it now. Through hands-on studio work, experiments, and design projects, we combined artistic expression with the science of glass—learning how physics and chemistry shape everything from color to strength and light interaction. The students have developed practical skills in cutting, grinding, foiling, soldering, and assembling stained-glass pieces, while also experimenting with thermal stress, light transmission, and color chemistry. Glass is now understood as not just as an art form, but as a dynamic material grounded in scientific …

What Do Black Holes Teach Us About Wigner’S Friend?, Emily Adlam

Mathematics, Physics, and Computer Science Faculty Articles and Research

Recently, Hausmann and Renner have pointed out that several famous paradoxes relating to black holes have a similar character to various Extended Wigner’s Friend paradoxes. In this paper I consider what the connection between these things could teach us about the Wigner’s Friend scenarios. I argue that if we take the analogy between these cases seriously, the black hole paradoxes appear to favour a certain class of response to the Wigner’s Friend scenario - specifically, those which posit intrinsic relationality, rather than effective and emergent relationality, and also those which posit some kind of retrocausality.

Reproducibility Of Carbon Quantum Dots, Liliana De Salas, Kyah Smalley, Nicholas Whiting

STEM Student Research Symposium Posters

Carbon quantum dots (CQDs) are semi-conducting, carbon- based, spherical nano-crystals known for their photo-luminescent properties and biocompatibility, making them intriguing candidates for nano fertilization of crop plants. Green synthesis of CQDs utilizes hydrothermal solvation. Synthesis of CQDs from agricultural wastes is a sustainable, low-cost alternative to other synthesis pathways

Intermediate-Scale Outflow Dynamics Of Eta Carinae, Edmund J. Garcia, Matthew C. Fleenor

Departmental Honors & Graduate Capstone Projects

η Carinae (η Car) is a binary system, with the larger star being an extremely massive, luminous blue variable (LBV) beyond the Eddington Limit. Surrounding the η Car system, numerous multi-wavelength imaging campaigns reveal axisymmetric structures with the expanding bipolar Homunculus Nebula (¡1 pc). In combination with the episodic eruptive history of the η Car system, our initial intermediate-scale imaging revealed further axisym- metric structures (1-5 pc). To gain a more expansive view of how the small scale structure connects to panoramic imaging of the η Car region, we constructed a deep, optical, narrowband mosaic of 189 images utilizing the …

Exactly Solving One-Dimensional Models For The Fractional Quantum Hall Effect, Joseph R. Cruise

Arts & Sciences Graduate Student Theses and Dissertations

Nearly fifty years after its experimental debut, the quantum hall effect has produced perhaps more unique descriptions than any other subject of condensed matter physics. From topological band theory to non-commutative geometry, topological and conformal field theories, random matrix models and more, each approach captures a subset of the essential features, and compliments the others to produce a beautiful mosaic description. In this thesis, we revisit the fractional quantum hall (FQH) effect from its oldest vantage point, that of the trial wavefunctions and the parent Hamiltonians which stabilize them. Laughlin's observation of the importance of the theory of holomorphic functions …

Theoretical Study Of Electronic Properties Of Functionalized Monolayers: Cu, Ag, Au, And Pt Atomic Wires On Graphene, H-Bn Monolayer, Silicene, And Phosphorene, Mythreyee T. Aasuri, Mukesh K. Choudhary, Narender Kumar, Ravindra Pandey

Michigan Tech Publications

The structural and electronic properties of graphene, h-BN monolayer, silicene, and phosphorene monolayers functionalized with Cu, Ag, Au, and Pt atomic wires were investigated using van der Waals─corrected density functional theory. These atomic wires form stable, functionalized monolayers that exhibit physisorption on planar monolayers and chemisorption on nonplanar ones. This results in either linear or bent configurations of the atomic wires, depending on the interface strength, leading to distinct electronic states. A weaker interface induces metal-induced gap states near the Fermi level, whereas a stronger interface results in covalently hybridized states farther from the Fermi level. Analysis of the electron …

Isolation, Identification And Antibiotic-Resistance Profiling Of Bacteria Isolated From Mobile Phone Surfaces In Karbala., Kawkab Abdullah Alsaadi, Zahraa Raheem Murshidy, Dhuha Ali Hussein, Sura Abd Ali Kadhim, Kawakib Aboudi Hanoon

Karbala International Journal of Modern Science

Due to the diverse environments that mobile phones are exposed to via human handling they become reservoirs of microorganisms. The objective of the current study was to determine the level and character of bacterial contamination on mobile phones by identifying bacterial strains, and the degree of antimicrobial susceptibility. A cross-sectional study was conducted from April to July 2025 where phones belonging to 115 individuals were randomly chosen from various departments and units at Kerbala University and swabbed. The VITEK 2 automated system was used to identify bacterial taxa and test for antimicrobial susceptibility, and 50 of the swabs exhibited bacterial …

An Infinite Set Of One-Range Addition Theorems Without An Infinite Second Series, For Slater Orbitals And Their Derivatives, Applicable To Multiple Coordinate Systems, Jack C. Straton

Physics Faculty Publications and Presentations

Addition theorems have been indispensable tools for the reduction of quantum transition amplitudes. They are normally utilized at the start of the process to move the angular dependence within plane waves, Coulomb potentials, and the like, into a sum over spherical harmonics that allows the angular integration to be carried out. These have historically been “two-range” addition theorems, characterized by the two-fold notation r>=Max[r1,r2] and r< =Min[r1,r2] and comprising a single infinite series. More recently, “one-range” addition theorems have been created that have no such piecewise notation, but at the cost of the introduction of another infinite series. We use a very different approach to derive an infinite set of addition theorems for Slater orbitals, hydrogenic and Hylleraas wave functions, and so on, that retain the one-range variable dependence but have, at worst, a finite second series rather than an infinite one. In addition, unlike previous addition theorems, they are applicable to more than one coordinate system. One of these addition theorems may also be used for Yukawa-like functions that may appear late in the reduction of amplitude integrals, and we show its utility for an integral that has stubbornly defied reduction to analytic form for nearly sixty years. Finally, we craft indefinite integrals of 15 half-integer Macdonald functions multiplied by (inverse) powers and negative exponentials containing squares of the integration variable.

The Role Of Interactions In Moiré Quantum Materials, Liangtao Peng

Arts & Sciences Graduate Student Theses and Dissertations

Moiré quantum materials have emerged as a highly tunable platform for studying strongly interacting electrons in low dimensions. By twisting or lattice-mismatching atomically thin crystals, one can generate long-wavelength moiré superlattices that reconstruct the electronic bands, produce narrow bandwidths, and greatly enhance the importance of Coulomb interactions. As a result, these systems host a wide range of correlated phenomena, including symmetry breaking, magnetism, and superconductivity. This dissertation develops and applies Green's-function-based many-body methods to understand the role of interactions in moiré quantum materials. This dissertation consists of four chapters. The first chapter introduces moiré quantum materials and reviews the basic …

Development Of New Technical Approaches To Speed The Search For Axion Dark Matter With Haloscopes, Jonah Harper Hoffman

Arts & Sciences Graduate Student Theses and Dissertations

The axion is a hypothetical particle that may solve two major problems in physics: the strong CP problem in quantum chromodynamics (QCD) and the unknown particle nature of the dark matter. Axion haloscopes like the Axion Dark Matter eXperiment (ADMX) are capable of probing the region of parameter space where axions could constitute the dark matter. These experiments use a microwave resonant cavity in a strong magnetic field to convert axions into detectable photons when their Compton wavelength matches the resonant mode of the cavity. By moving a metal rod within the cavity volume, the resonant frequency can be tuned, …

Static And Dynamic Properties Of Dense Matter, Liam Brodie

Arts & Sciences Graduate Student Theses and Dissertations

Neutron stars and their mergers create environments of ultra-dense matter where the strong interaction governs the behavior, but where quantum chromodynamics, the theory of the strong interaction, cannot be solved exactly or perturbatively using current methods. Neutron stars are objects with more mass than our Sun, but with a diameter of about 25 km. Observations of neutron star macroscopic properties like their masses and radii, their surface temperatures, and the gravitational-wave and electromagnetic signals from their mergers allow us to use theoretical tools to infer the behavior of matter at a microscopic scale. In this thesis, we explore the static …

Advancing High-Energy Astrophysics Through X-Ray Spectropolarimetry And Balloon-Borne Instrumentation, Sohee Chun

Arts & Sciences Graduate Student Theses and Dissertations

The strong gravitational field around black holes provides a unique laboratory for investigating the behavior of matter and radiation under extreme conditions. As matter accretes, the interplay between the accretion disk, hot corona, and surrounding stellar environment produces complex spectral and polarimetric X-ray signatures. Thus, X-ray spectropolarimetry has become a powerful tool for constraining the accretion geometry. Building on these advances, this dissertation integrates theoretical modeling, observational data analysis, and instrumentation development to address open questions in high-energy astrophysics. On the theoretical side, relativistic ray-tracing simulations test the truncated disk-hot inner flow accretion geometry against observations of Cygnus X-1, identifying …

3Ω Thermal Transport In Atomically Thin Materials, Yiwei Le

Arts & Sciences Graduate Student Theses and Dissertations

Since the discovery of graphene, research on two-dimensional (2D) materials has become a central focus of condensed matter physics. While an enormous number and variety of investigations of their electrical, optical, and mechanical properties have been undertaken, their thermal properties remain comparatively underexplored, despite the importance for understanding low-energy excitations and phase transitions. Here, we introduce an extension of the 3ω method thermal measurement technique to the 2D limit of materials. We develop analytical models of thermal transport in the 3ω geometry with boundary conditions tailored for suspended 2D flakes. We then experimentally confirm the feasibility of this approach in …

All-Sky Search For Long-Duration Gravitational-Wave Transients In The First Part Of The Fourth Ligo-Virgo-Kagra Observing Run, A. G. Abac, I. Abouelfettouh, F. Acernese, Teviet Creighton, Mario C. Diaz, Raul A. Espinosa, J. Lawrence, Francisco Llamas Villarreal, Soma Mukherjee, Volker Quetschke, Miriam Ramos Arevalo, Wenhui Wang

Physics & Astronomy Faculty Publications

We present an all-sky search for long-duration gravitational waves (GWs) from the first part of the LIGO-Virgo-KAGRA fourth observing run (O4), called O4a and comprising data taken between May 24, 2023, and January 16, 2024. The GW signals targeted by this search are the so-called “long-duration” ( ≳1  s) transients expected from a variety of astrophysical processes, including nonaxisymmetric deformations in magnetars or eccentric binary coalescences. We make minimal assumptions on the emitted GW waveforms in terms of morphologies and durations. Overall, our search targets signals with durations of ∼1–1000  s and frequency content in the range 16–2048 Hz. In …

The True Interstellar Anisotropy Of 13 Tev Cosmic Rays, Matthew Conde

Aerospace, Physics, and Space Science Student Publications

Cosmic rays (CRs) are high-energy particles; bare atomic nuclei, with varying origins and energy levels. Research in this field is focused on identifying potential origins, understanding transport mechanisms faced on their journey to Earth, and interpreting the angular structure of incident CRs. One obstacle of this research is the trajectory modulation induced by the heliosphere during the CRs’ journey. In this work we employ a method to reconstruct the properties of CRs as they were at the local interstellar medium (LISM) by means of a nonlinear model fit to the map at Earth. Another obstacle is the time-averaging used to …

Gamma Ray Burst Afterglow Slopes, Brian Robbins

Aerospace, Physics, and Space Science Student Publications

The standard models for gamma ray bursts (GRBs) typically assume that shockaccelerated electrons follow a power law distribution of energies. However, this behavior is not what some gamma ray bursts show. In this project, it is suggested that the presence of thermal electrons causes temporal and spectral structure across the afterglow, which is significantly different from models assuming a pure power-law distribution of electrons. To model the afterglows, we decide on a large number of samples of GRBs from the Swift database and obtain the temporal and spectral indices at arbitrary times. By finding the temporal and spectral indices at …

Dual-Lev: A Dual-Axis Ultrasonic Acoustic Levitator, Trevor Hennington, Alyx Mason

Aerospace, Physics, and Space Science Student Publications

sound waves to create a standing wave, where regions of high and low pressure form stable nodes that can trap small objects. The upward acoustic radiation force at these nodes balances gravity, allowing the object to float in midair. This technology is applicable in various fields such as chemistry, biological engineering, and sub-gravity simulation. It can also be used for drop dynamics studies, crystallization, and

Electron Emission From Unactivated Gaas: Towards The Development Of Novel Sources Of Spin-Polarized Electrons, William Truslow Newman

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Spin-polarized electrons are commonly emitted from GaAs photocathodes with treated surfaces in a process called negative electron affinity activation. These sources require stringent vacuum conditions that are often hard to achieve and lead to significant downtimes in experiments. In this dissertation, I present new investigations of electron emission from unactivated GaAs towards the development of novel sources of spin-polarized electrons. The work entails two primary directions. The first is the investigation of electron emission using multiphoton ionization processes enhanced by nanoscale surface structures. We explore GaAs electron sources including, shards, nanotip arrays of pyramid structures, wedges, and ion-milled tips. The …

High Performance Ae-Cnn Model Enhanced Via Gaussian Augmentation For Rssi-Dependent Indoor Positioning In Wireless Sensor Networks, Kahlaa K. Al-Nassrawy, Ghaidaa A Al-Sultany

Karbala International Journal of Modern Science

Precise indoor positioning system remains a significant challenge within Wireless Sensor Networks (WSNs) due to the instability and noise sensitivity of Received Signal Strength Indicator (RSSI) data. This paper proposes an advanced hybrid deep learning framework designed for 2D indoor localization, utilizing RSSI measurements to predict human or object position. Furthermore, to enhance the robustness of the model against signal variance and promote its generalization capability under this uncertainty, a data augmentation strategy is applied using three methods: Gaussian Noise Injection (GNI), Gaussian Mixture Model (GMM), and Bayesian Gaussian Mixture Model (BGMM). The purpose of data augmentation is to simulate …

Optimization Of Pediatric Multidetector Ct Imaging Parameters Using A Machine Learning–Based Monte Carlo Simulation Model, Ali O. Masoud, Adithya Rajnaryanan, Khamis O. Amour, Ahmed M. Jusabani, Justin E Ngaile, Manoj Kumar, Mwingereza John Kumwenda Dr

Tanzania Journal of Science

This study utilized Monte Carlo (MC) simulations to optimize radiation doses in pediatric multidetector computed tomography (MDCT) head scans by analyzing key parameters like tube current (mA), tube voltage (kV), pitch, and slice thickness. The findings indicate that reducing tube current significantly lowers the Computed Tomography Dose Index (CTDIvol) and Dose Length Product (DLP), effectively minimizing patient radiation exposure. Higher pitch values (0.7–0.9) further reduced radiation by decreasing beam overlap, while using a thinner slice thickness (0.6 mm) improved dose efficiency. A comparison highlighted the effectiveness of optimization: simulated parameters kVp 100, mAs 81, pitch 0.98 yielded a CTDIvol of …

Developing Physics And Computing Identities In A Computationally Integrated Physics Course, Elizabeth Hallock

Engineering & Physics Student Scholarship

No abstract provided.

Spot Scanning Proton Beams Characterization Via Plastic Scintillator Detector, Saad Bin Saeed Ahmed

Electronic Theses and Dissertations

In spot scanning proton therapy, the machine steers magnetically a narrow pencil beam across the target volume, delivering highly conformal dose distributions layer by layer. As beam size is very small, this introduces a dosimetry problem. The beam is dynamic and the dose gradients are steep — conditions that push conventional ionization chambers beyond their reliable operating range. Plastic scintillation detectors offer a potential solution. Their sub-millimeter active volumes avoid the volume-averaging effects over larger chambers, and their very high temporal resolution making real-time monitoring feasible. This thesis characterizes the Blue Physics plastic scintillation detector in spot scanning proton fields …

Patient-Level Breast Cancer Classification From Multi-View Mammography With Side-Specific Evidence For Interpretability, Bushra Intakhab

Electronic Theses and Dissertations

Breast cancer remains one of the leading causes of cancer-related death among women. Early detection through screening mammography is therefore very important. However, mammogram interpretation can be difficult because abnormalities may be subtle and spread across different views. The increasing workload of radiologists can also affect timely analysis. Artificial intelligence (AI) has been widely explored to support mammography interpretation by improving speed and consistency. However, many existing AI methods focus on patch-level or image-level analysis rather than the full patient exam. This limits their ability to capture the complete clinical picture, since important information is distributed across multiple views. In …

Development And Flight Of Stratospheric Missions For Hard X-Ray Polarimetry And Hard X-Ray Spectroscopy, Ephraim Gau

Arts & Sciences Graduate Student Theses and Dissertations

The recent launches of the {\it Imaging X-ray Polarimetry Explorer} ({\it IXPE}\,) and {\it XRISM} have provided significant advances to the realms of polarization and high-resolution spectroscopy in X-ray astrophysics. However, both of these satellite missions conduct measurements in the soft X-rays, below 10 keV. To obtain a complete picture of any astrophysical source, we must extend these capabilities to the hard X-rays, above 10 keV, as well. Thus, in my graduate work, I have directed my efforts in these two regimes: measuring the polarization of hard X-rays with {\it XL-Calibur}, and improving the energy resolution of hard X-ray telescopes …