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California Polytechnic State University, San Luis Obispo

Physics

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Full-Text Articles in Physics

Non-Relativistic Limit Of Selected Terms From The Sme Dirac Lagrangian, Quinn Reece Mar 2024

Non-Relativistic Limit Of Selected Terms From The Sme Dirac Lagrangian, Quinn Reece

Physics

We examine a selection of individual CPT/Lorentz violating terms present in the relativistic lagrangian for a free spin- 1 2 Dirac fermion of mass m in the Standard Model Extension. Euler-Lagrange relations will be applied to give Dirac-like equations including these terms and a novel procedure will be used to generate non-relativistic limits of these equations which are Schr¨odinger-Pauli-like equations. These equations will be analyzed using classical quantum mechanics toy problems to gain physical intuition for the effects of the CPT violating terms, and the results will be discussed. We will conclude with discussion on future work will include the …


A Monte-Carlo Simulation Of Gamma Rays In A Sodium Iodide Detector, Ben Kessler Jun 2023

A Monte-Carlo Simulation Of Gamma Rays In A Sodium Iodide Detector, Ben Kessler

Physics

Gamma rays principally interact with matter through Compton scattering, photoelectric effect, pair production, and triplet production. The focus of this simulation is to study the theoretical energy spectrum created by gamma rays from a Cesium-137 source, which produces gamma photons with an energy of 0.662 MeV. At this energy level, most interactions are results of Compton scatters and the photoelectric effect. Therefore, this simulation only models those two effects on gamma rays. Using Monte Carlo methods and the Metropolis algorithm to sample the probability distributions of the two effects allowed for the simulation of gamma rays in a Sodium Iodide …


Diffusion-Driven Aggregation Of Particles In Quasi-2d Membranes, Oscar Gullickson Rausis Jun 2023

Diffusion-Driven Aggregation Of Particles In Quasi-2d Membranes, Oscar Gullickson Rausis

Physics

Many biological membranes can be modeled as two-dimensional (2D) viscous fluid sheets surrounded by three-dimensional (3D) fluids of different viscosity. Such membranes are dubbed quasi-2D as they exhibit properties of both 2D and 3D fluids. The Saffman length is a parameter that describes the energy exchange between the membrane and bulk fluids and controls the cross-over from 2D to 3D hydrodynamics. We aim to model diffusion-driven aggregation of particles embedded in a quasi-2D membrane. It is known that hydrodynamic interactions between solute particles significantly reduce their aggregation rate in 3D fluids. It is expected that in quasi-2D membranes the reduction …


Optimization Of Flagellar Locomotion In The Low Reynolds Number Regime, Aidan M. Trodden, Aidan M. Trodden Jun 2023

Optimization Of Flagellar Locomotion In The Low Reynolds Number Regime, Aidan M. Trodden, Aidan M. Trodden

Physics

This report investigates the computational and theoretical techniques - modeled by E. Lauga and C. Eloy - used to optimize the shape of an activated flagellum for enhanced cell motility. Cell motility is ubiquitous and has a large affect on biological systems such as marine life ecosystems, reproduction, and infection. The physical principles governing flagellar propulsion are explored using computational fluid dynamics simulations, mathematical modeling, and the sequential quadratic programming (SQP) optimization algorithm. Through iterative refinement, we can identify optimized flagellar shapes that would minimize the energetic cost dependent on a single dimensionless sperm numbers (Sp). The computation of the …


Optimizing Solid Thermal Storage In Insulated Solar Electric Cookers, Stefan Avramov Jun 2023

Optimizing Solid Thermal Storage In Insulated Solar Electric Cookers, Stefan Avramov

Physics

Insulated Solar Electric Cookers, more commonly known by their acronym ISECookers, are an alternative to biomass cooking. The ISECooker in its simplest form is a solar panel connected to a heating element, in contact with a cooking pot in an insulated chamber. An aluminum puck can be heated as solid thermal storage (STS) for increased power and night time cooking. Power was limited to about 500 W by the interface between the STS and cookpot. Powdered graphite and silver were separately applied to increase thermal flow. However, the powdered graphite decreased the thermal flow, while powdered silver decreased the temperature …


Building Structures From Mycelium, Noah M. Brown Dec 2022

Building Structures From Mycelium, Noah M. Brown

Physics

The purpose of this project was to develop a method for creating bricks from mycelium and agricultural waste. The bulk of the research happened in two parts, the first part being a period in which different substrates, strains, and methods were used build the bricks. This research took place in San Luis Obispo and was aided by a group of students in PSC392 under Dr. Pete Schwartz in early 2022. After developing a method for constructing these bricks, the research was moved to St. Thomas, Jamaica, in collaboration with an ecovillage called The Source Farm from July to September. The …


Thermal Degradation Of Erythritol, Sudheendra Gamoji Nov 2022

Thermal Degradation Of Erythritol, Sudheendra Gamoji

Physics

The Insulated Solar Electric Cooker (ISEC) is a double walled Aluminum pot with a resistive heater directly connected to a solar panel whose goal is to create and disseminate cheap solar cookers in rural areas that primarily rely on biomass for cooking. Phase Change Materials (PCMs) like Erythritol, a sugar substitute, take a tremendous amount of energy to melt, and when they solidify they release the energy. Through the use of PCMs, the ISECs will produce enough heat to cook food even after the sun sets. However, PCMs like Erythritol degrade over repeated heat exposure, so the purpose of this …


An Inexpensive Maximum Power Point Tracking System For An Insulated Solar Electric Cooker Using An Off-The-Shelf Buck Converter, Andrew A. Perez Sep 2022

An Inexpensive Maximum Power Point Tracking System For An Insulated Solar Electric Cooker Using An Off-The-Shelf Buck Converter, Andrew A. Perez

Physics

A specialized control circuit using an off-the-shelf buck converter is built for an Insulated Solar Electric Cooker (ISEC). Cost and efficient power delivery are the focus. An ISEC is synonymous to a direct load heat resistor, allowing a specific maximum power point tracking (MPPT) algorithm and fewer components. Only a microcontroller, voltage sensor, and digital-to-analog converter are used with the buck converter to maximize the power delivered by a 100W solar panel for the 3.3Ω load.


Developing Positive Thermal Coefficient (Ptc) Heaters For Solar Electric Cooking, Katarina Ivana Brekalo, Andrew Shepherd Sep 2022

Developing Positive Thermal Coefficient (Ptc) Heaters For Solar Electric Cooking, Katarina Ivana Brekalo, Andrew Shepherd

Physics

Positive Thermal Coefficients, PTCs, are materials that abruptly change in resistance in response to changes in temperature. The purpose of this experiment is to explore the viability of using the switching type ceramic PTC thermistor as a replacement for current resistive heaters. These types of PTCs have a nonlinear change in resistance with increases in temperature. This device will be used as a temperature-controlling heating element intended to power an Insulated Solar Electric Cooker (ISEC). The ISEC is designed to cook meals throughout the day for impacted communities as an alternative cooking method that doesn’t require biofuel as an energy …


Developing A Data Acquisition System For Use In Cold Neutral Atom Traps, Jonathan E. Fuzaro Alencar Jun 2022

Developing A Data Acquisition System For Use In Cold Neutral Atom Traps, Jonathan E. Fuzaro Alencar

Physics

The rising interest in quantum computing has led to new quantum systems being developed and researched. Among these are trapped neutral atoms which have several desirable features and may be configured and operated on using lasers in an optical lattice. This work describes the development of a new data acquisition system for use in tuning lasers near the precise hyperfine transition frequencies of Rb 87 atoms, a crucial step in the functionality of a neutral atom trap. This improves on previous implementations that were deprecated and limited in laser frequency sweep range. Integration into the experiment was accomplished using an …


Solid Thermal Storage As An Energy Storage Device In Insulated Solar Electric Cookers: Thermal Modeling And Experiment, Michael Antonio Fernandez Jun 2022

Solid Thermal Storage As An Energy Storage Device In Insulated Solar Electric Cookers: Thermal Modeling And Experiment, Michael Antonio Fernandez

Physics

The use of solid thermal storage (STS) as an energy storage device in insulated solar electric cookers (ISEC) was explored using a thermal simulation before retrofitting an existing cooker without energy storage and testing it under several conditions. STS sizing, material selection, and geometry were examined from both theoretical and practical perspectives and re-examined following experimental results. Characterization of the system’s thermal interfaces and methods to improve their thermal conductivities were investigated resulting in several performance enhancements to the system.


Quantum Key Distribution Simulation Using Entangled Bell States, Nayana Tiwari Jun 2022

Quantum Key Distribution Simulation Using Entangled Bell States, Nayana Tiwari

Physics

To communicate information securely, the sender and recipient of the information need to have a shared, secret key. Quantum key distribution (QKD) is a proposed method for this and takes advantage of the laws of quantum mechanics. The users, Alice and Bob, exchange quantum information in the form of entangled qubits over a quantum channel as well as exchanging measurement information over a classical channel. A successful QKD algorithm will ensure that when an eavesdropper has access to both the quantum and classical information channels, they cannot deduce the key, and they will be detected by the key generators. This …


Automation Of The Transition Identification Procedure For Trapping Rubidium Atoms In A Magneto-Optical Trap, Michael P. Fletcher May 2022

Automation Of The Transition Identification Procedure For Trapping Rubidium Atoms In A Magneto-Optical Trap, Michael P. Fletcher

Physics

The words “quantum computer” often conjure images of science fiction and unrealistic technology from an impossible future. Some may even believe that they aren’t real or are only theoretical. The truth is that quantum computers are real, tangible systems with real life uses and rooted in credible scientific research. Today, many groups of scientists collaborate on research into better ways of implementing and improving quantum computing techniques. This paper will be addressing the systems required and phenomena used to achieve neutral atom trapping for quantum computation. This thesis will outline the physical phenomena involved with the frequency tuning process for …


Energy Analysis For Neutron Induced Ternary Fission Events In The Niffte Fission Time Projection Chamber, Vanessa Aguilar Apr 2022

Energy Analysis For Neutron Induced Ternary Fission Events In The Niffte Fission Time Projection Chamber, Vanessa Aguilar

Physics

In this paper, energy analyses were made for investigating ternary fission in neutron-induced fission of U235 and U238 using the Neutron Induced Fission Fragment Tracking Experiment (NIFFTE) collaboration’s fission time projection chamber (TPC) data. The Neutron kinetic energy was calculated from neutron time of flight (nToF) for energy ranges of 0.1 to 32 MeV. Along with this, the Stopping and Range of Ions in Matter (SRIM) software was used to simulate alphas going through an argon gas target in order to calibrate observed energy loss of alphas from ternary fission.


Memory Capacity In A System Of Swelling Particles, David T. Keating Mar 2022

Memory Capacity In A System Of Swelling Particles, David T. Keating

Physics

A system has the ability to store memory if one is able to write, retrieve, and erase information from it. Some systems are capable of storing multiple transient memories; with no noise in these systems, at long time, the memories degrade until one or two remain. The addition of noise to these systems can extend the retention of multiple memories, in some cases indefinitely [2, 3]. While this behavior was first observed in simulations of charge density waves, it has since appeared in other systems [1].

Past research has shown that sheared non-Brownian liquid suspensions of particles exhibit similar behavior …


Rigid Aggregation Of Inclusions Embedded In Quasi 2d Fluids, Natalie Xochitl Ryan Dec 2021

Rigid Aggregation Of Inclusions Embedded In Quasi 2d Fluids, Natalie Xochitl Ryan

Physics

Diffusion is a transport process common in several biological systems. In this process particles of different species mix together through random (stochastic) motion at molecular length scales. Diffusion in fluids is unique as the coupling of the flow and fluid have been found to produce giant concentration fluctuations. The molecular length scale of these concentration fluctuations are magnitudes larger than the movement of the particles themselves, earning them the title “giant”. The diffusion of particles in bio-membranes displays a combination of 2D and 3D hydrodynamic properties; the movements of the particles are restricted to the plane of the membrane and …


Plasma-Laser Wakefield Acceleration, Jonathan Babu Dec 2021

Plasma-Laser Wakefield Acceleration, Jonathan Babu

Physics

Many texts detailing the derivations and science of Wakefield Acceleration are aimed at graduate and doctorate level scholars, and these may seem intimidating to new physics students. This paper is meant to be an introduction to the nature of plasmas, lasers, laser-plasma interactions, and Laser Wakefield Acceleration (LWFA), with sources given where extra detail may be required. I recognize that this paper is not meant to be an all-encompassing review on the nature of the topics, as these topics are complex and subject of entire textbooks. Instead, I aim to provide an introduction to these topics to a college-level scholar …


Lorentz Violations And The Casimir Effect, Samuel G. Christensen Dec 2021

Lorentz Violations And The Casimir Effect, Samuel G. Christensen

Physics

The background and calculation for the corrections to the Casimir Energy stored on parallel conducting plates due to minimal violations of Lorentz invariance are presented as a test of the Standard Model. A direction-dependent photon dispersion relation using operators of dimension 4 and higher is used in the calculation of the spacetime anisotropy correction terms to the Casimir energy. The calculation includes discussion of Riemann zeta function regularization and its equivalence to Euler-Maclaurin sum-integral formulas in a Casimir effect calculation. The two plate geometry result is mapped onto a one plate and sphere geometry to cater to modern precision tests …


Swarming Oscillators With Time-Delayed Interactions, Nicholas S. Blum Dec 2021

Swarming Oscillators With Time-Delayed Interactions, Nicholas S. Blum

Physics

We investigate the role of delay in the collective dynamics of particles that swarm in space and possess an internal oscillatory degree of freedom, called swarmalators. Swarmalators were introduced recently by O’Keeffe, Hong, and Strogatz in Nature Communications 8, 1504 (2017). The addition of a time delay into the system of swarmalators was motivated by the biology of early embryonic development. This delay leads to a rich phenomenology, which includes two new collective states, which we call "semi-static crystal" and "boiling". In the semi-static crystal state, all particles in a cluster undergo decaying radial oscillations completely in phase with one …


Modeling Cherenkov Light Detection Timing For The Very Energetic Radiation Imaging Telescope Array System, Keilan Finn Ramirez Dec 2021

Modeling Cherenkov Light Detection Timing For The Very Energetic Radiation Imaging Telescope Array System, Keilan Finn Ramirez

Physics

The Very Energetic Radiation Imaging Telescope Array System (VERITAS) is an array of four 12-meter telescopes which use the Imaging Atmospheric Cherenkov Technique to conduct high-energy gamma-ray astronomy. VERITAS detects magnitude and location information associated with Cherenkov light, and uses this information to indirectly observe gamma-rays through a software reconstruction process. VERITAS also records timing information corresponding to Cherenkov light detection, and this additional information could theoretically be incorporated into the reconstruction process to improve the accuracy of gamma-ray observations. The first step to including timing information is to understand when Cherenkov light detection would be expected from a known …


Rapid Warming Events In A Small Coastal Upwelling Embayment, Tatjana E. Ellis Jun 2021

Rapid Warming Events In A Small Coastal Upwelling Embayment, Tatjana E. Ellis

Physics

Temperature variability in the nearshore coastal ocean influences various biological processes and can drive changes in biodiversity and habitat range. Despite recent progress, there are still significant gaps in the understanding of drivers of temperature variability in upwelling bays, particularly at higher frequencies. In this study, we analyzed a decade of nearshore temperature measurements both inside and outside a small coastal embayment located in central California [San Luis Obispo (SLO) bay], as well as temperature data from satellites, to characterize rapid warming events. We found that rapid warming events, defined using rates of temperature change across different thresholds, occurred more …


Direct Drive Solar Panel Control Circuit, Marcorios Bekheit May 2021

Direct Drive Solar Panel Control Circuit, Marcorios Bekheit

Physics

A control circuit is built for insulated solar electric cookers (ISEC). Power delivery and temperature safety are the focus. Using a maximum power point tracking (MPPT) algorithm, Arduino Nano, voltage and current sensors, and a buck converter, the solar panel’s output power was maximized for a direct load heat resistor with 3.5Ω for a range of solar intensities. Using a resistance temperature detector, a temperature sensor is built for safety shutoff.


Quantum Computing: Resolving Myths, From Physics To Metaphysics, Jacob R. Mandel Mar 2021

Quantum Computing: Resolving Myths, From Physics To Metaphysics, Jacob R. Mandel

Physics

As the field of quantum computing becomes popularized, myths or misconceptions will inevitably come along with it. From the sci-fi genre to the casual usage of the term quantum, idealism begins to take over our projections of the technological future. But what are quantum computers? And what does quantum mean? How are they any different than the computers we use on an everyday basis? Will there be quantum computing smartphones? Are quantum computers just a faster version of conventional computing or a wholly new way of computing altogether? The objective of this paper is to resolve common myths or misconceptions …


Lorentz Violation In Neutrino Interactions, Pranav Jayaram Seetharaman Mar 2021

Lorentz Violation In Neutrino Interactions, Pranav Jayaram Seetharaman

Physics

Both the Standard Model of particle physics and General Relativity require Lorentz symmetry as a fundamental building block. In this paper, we learn about a framework called the Standard Model Extension that allows us to determine how physical phenomenon would change if we deviated from Lorentz invariance in the Standard Model and General Relativity. We use the Standard Model Extension to analyze a specific high-energy, astrophysical neutrino interaction that is only possible if Lorentz symmetry can be broken. The interaction we look at is the decay of a neutrino into an electron-positron pair, which is not possible in conventional physics. …


The Structure Function Relationship Of Disordered Networks Using Young's Modulus And Floppy Modes, Melinda Grace Tajnai Feb 2021

The Structure Function Relationship Of Disordered Networks Using Young's Modulus And Floppy Modes, Melinda Grace Tajnai

Physics

Disordered networks may have the ability to store information that can be retrieved using a Young’s modulus measurement. The effect of the number of floppy modes a network has on the value of this Young’s modulus measurement is unknown. This experiment uses 28 networks consisting of 3D printed edges in a sliding frame to determine how the Young’s modulus of a network is related to the number of floppy modes.


Using Current-Voltage Characteristics To Probe The Transport Mechanism In Carbon Nanotube Networks, Alejandro Jimenez Nov 2020

Using Current-Voltage Characteristics To Probe The Transport Mechanism In Carbon Nanotube Networks, Alejandro Jimenez

Physics

Carbon nanotube (CNT) random networks have shown great promise in electronic applications. For example, they have been used as the active layer in thin film transistor biosensors and as electrodes in supercapacitors (Hu, 2010). Although CNT networks applications are numerous, some of the key details of their electrical behavior are not fully understood. In particular, it is known that the junctions between tubes in CNT networks play a key role in determining the sensing properties of the network (Thanihaichelvana, et al., 2018), however, the mechanism by which metallic-semiconducting (m-s) tube junctions affect the electrical sensing properties of the network is …


Variability Of Active Galactic Nuclei From Differential Photometry, Nicholas Steven Yee Sep 2020

Variability Of Active Galactic Nuclei From Differential Photometry, Nicholas Steven Yee

Physics

The Seoul AGN Monitoring Project, or SAMP for short, is an international project (PI Jonghak Woo from Korea) with the goal of measuring the masses of black holes residing in the center of massive active galactic nuclei (AGNs). AGNs are some of the brightest objects in the universe. Their light is attributed to the accretion of material onto the black hole. However, these objects are too distant to spatially resolve the gravitational sphere of influence of the black hole directly. Instead, we use a technique called reverberation mapping which observes the variability of the AGN power-law continuum emission and the …


Cooking Systems Using Aluminum Foam, Ryan Tetsuo Mizukami Aug 2020

Cooking Systems Using Aluminum Foam, Ryan Tetsuo Mizukami

Physics

In developing countries, the use of wood burning fires for cooking is cause for illness and death. With this in mind, research was conducted to develop a solar cooking device capable of cooking of soup within 15 mins in order to reduce the negative impacts of cooking with wood. Current methods of solar-based cooking, such as solar concentrators and solar tube ovens, are impractical. A small solar panel is a cost-effective way to produce energy but will not produce enough power to cook within a reasonable amount of time. Even if it is assumed that all of the energy produced …


Learning Assistant And Instructor Communication: Impacts On Perceived Efficacy, Jahangir Rassouli, Laura Ríos Jul 2020

Learning Assistant And Instructor Communication: Impacts On Perceived Efficacy, Jahangir Rassouli, Laura Ríos

Physics

The Learning Assistant (LA) Model was co-developed by Richard McCray and Valerie Otero at the University of Colorado Boulder in 2003. In this model, senior undergraduate students serve as facilitators for group discussion in lower-division courses, and employ evidenced-based practices for promoting inquiry and active learning [1]. Since its inception, the LA model has grown to various departments, disciplines, and universities.

At California Polytechnic State University San Luis Obispo (Cal Poly), the LA program in the physics department is still in its early stages. As such, it is an environment rich for exploration into the affordances, limitations, and benefits of …


Corrosion Prevention, Matthew Walker Jun 2020

Corrosion Prevention, Matthew Walker

Physics

In Insulated Solar Electric Cooking (ISEC), heating is done by passing current through a chain of diodes directly connected to a solar panel (Gius et al, 2019). It is crucially important that the wires remain conducting, but not conduct to any metal surface that might short the heating circuit. Corrosion of any wires will cause a loosening of the mechanical (twisted) wire connection and could result in a loss of electrical connection completely, or undesired increased resistance.