Physics Commons^™

Questioning Reality: The Progressive Development Of Modern Physics, Joshua Lancman

STEM for Success Showcase

Humanity has a tendency to divide time. The past is distinct from the present which is entirely separate from the future. In supposedly 20-20 vision history is neatly divided into different sections, distinct eras with sharp lines between them. What is present and in the future is always modern. What is past is something else with another name.

Yet time is not divided so neatly. We know this living through it: years and decades blend into one another in a non-uniform progression. To divide human history into separate eras is a necessary simplification, as it helps to ascribe order onto …

Language, Coded Instructions And The Interaction With Thermodynamics, Andy C. Mcintosh

Proceedings of the International Conference on Creationism

The theme of the 9th ICC is Developing and Systematizing the Creation Model of Origins. Following this theme, the proposed paper seeks to establish a rigorous and systematic approach to the important area of information and its interface with the substrate on which the information is expressed. This must first involve the understanding of the laws of thermodynamics not only for isolated systems but for closed (where only energy is allowed to cross the boundary) and open systems (where both matter and energy are allowed to cross the boundary). This is particularly an issue with the second law of …

More On The Demons Of Thermodynamics, Daniel P. Sheehan, Garret Moddel, James W. Lee

Chemistry & Biochemistry Faculty Publications

No abstract provided.

Ds2 As Excitation Of Ads2, Florian Ecker, Daniel Grumiller, Robert Mcnees

Physics: Faculty Publications and Other Works

Title- dS₂ as excitation of AdS₂

We introduce a family of 2D dilaton gravity models with state-dependent constant curvature so that dS₂ emerges as an excitation of AdS₂. Curiously, the strong coupling region corresponds to the asymptotic region geometrically. Apart from these key differences, many features resemble the Almheiri–Polchinski model. We discuss perturbative and non-perturbative thermodynamical stability, bubble nucleation through matter shockwaves, and semiclassical backreaction effects. In some of these models, we find that low temperatures are dominated by AdS₂ but high temperatures are dominated by dS₂, concurrent with a recent proposal …

Development Of Graphical Models And Statistical Physics Motivated Approaches To Genomic Investigations, Yashwanth Lagisetty

Dissertations & Theses (Open Access)

Identifying genes involved in disease pathology has been a goal of genomic research since the early days of the field. However, as technology improves and the body of research grows, we are faced with more questions than answers. Among these is the pressing matter of our incomplete understanding of the genetic underpinnings of complex diseases. Many hypotheses offer explanations as to why direct and independent analyses of variants, as done in genome-wide association studies (GWAS), may not fully elucidate disease genetics. These range from pointing out flaws in statistical testing to invoking the complex dynamics of epigenetic processes. In the …

Symmetry And Control In Thermodynamics, Emily Adlam, L. Uribarri, N. Allen

Mathematics, Physics, and Computer Science Faculty Articles and Research

We explore the relationship between symmetry and entropy, distinguishing between symmetries of state and dynamical symmetries, and in the context of quantum thermodynamics between symmetries of pure and mixed states. Ultimately, we will argue that symmetry in thermodynamics is best understood as a means of control within the control theory paradigm, and we will describe an interesting technological application of symmetry-based control in the context of a quantum coherence capacitor. Symmetry, the concept from which Noether derived the conservation laws of physics, is one of the most important guiding principles of modern physics. Moreover, symmetry is often regarded as a …

Investigating The Thermodynamics And Seismic Profile Of The Europan Hydrosphere Through Pure-Water Modeling And Saltwater Experiments, Samantha Rosenfeld

Honors Theses

We explore the properties of the hydrosphere on Europa involving both a modeling technique and experimental methods. We perform a computational analysis of the thermodynamic properties for an ideal, pure-water Europan ice shell using a Python programming framework called SeaFreeze. We create four models assuming surface temperatures of either 50 K or 140 K and ice shell thicknesses of either 3 km or 30 km. We observe mostly linear trends for the density and seismic wave velocities with respect to depth and find that surface temperature has the greatest effect on the models. Simultaneously, we experimentally investigate the phase diagram …

Relationship Between Thermal Conductivity And Free Electrons In Metal, Yansong Liu

Senior Theses

An experiment was designed and conducted to explore the relationship between thermal conductivity with free electrons in metal. In the experiment, copper, iron, aluminum, and titanium rods with close diameters were used to carry out the experiment. Each rod was heated up by a heat unit at one end while cooled on the other end with a heat sink to maintain a steady state. DC current was applied to rods in the direction along, as well as against, the heat flow. Thermal conductivities were measured in these two situations for each rod. Results showed electrons do dominate thermal flow inside …

Predicting The Hydration Free Energy Of Small Alkanes And Alcohols From Custom, Electronic Structure-Based Force Fields, T. Ryan Rogers

Graduate Theses and Dissertations

Mathematical theories reveal the fundamental physics involved in experimentalphenomena. Computer models of such theories are routinely used to corroborate or explain experiments and predict properties of chemical systems. Therefore, an important effort in computational chemistry is the development of more accurate and efficient chemical models. Current-generation models are only beginning to approach experimental-quality predictions of hydration free energies (HFEs).Using computations of quantum mechanical (QM) forces and classical simulations based on these forces, I investigate models to predict several properties of solutes and solutions. This dissertation is a collection of projects exemplifying methods used to gain insight into chemical systems.

Simulations …

Protein Conformational Entropy Is Not Slaved To Water, Bryan S Marques, Matthew A Stetz, Christine Jorge, Kathleen G Valentine, A Joshua Wand, Nathaniel V Nucci

Faculty Scholarship for the College of Science & Mathematics

Conformational entropy can be an important element of the thermodynamics of protein functions such as the binding of ligands. The observed role for conformational entropy in modulating molecular recognition by proteins is in opposition to an often-invoked theory for the interaction of protein molecules with solvent water. The "solvent slaving" model predicts that protein motion is strongly coupled to various aspects of water such as bulk solvent viscosity and local hydration shell dynamics. Changes in conformational entropy are manifested in alterations of fast internal side chain motion that is detectable by NMR relaxation. We show here that the fast-internal side …

Specificity Of Ssb Binding To Its Interacting Proteins And Multiple Allosteric Effects Of Ssb C-Terminal Tail On Assembly And Dna Binding Of E. Coli Recor Proteins, Min Kyung Shinn

Arts & Sciences Electronic Theses and Dissertations

The homo-tetrameric E. coli single strand (ss) DNA binding (SSB) protein is an essential component in DNA maintenance for its role in binding and protecting single stranded DNA intermediates via its N-terminal DNA binding domain (DBD). SSB also acts as a hub to recruit at least 17 SSB interacting proteins (SIPs) involved in DNA replication, recombination, and repair via its 9 amino acid C-terminal acidic tip region. A 56 amino acid intrinsically disordered linker connects the DBD and the acidic tip and plays a role in cooperative binding to ssDNA. Using isothermal titration calorimetry, I determined that the SSB-Ct peptides …

The Crisis Of Communication In The Information Age: Revisiting C.P. Snow's Two Cultures In The Era Of Fake News, Aaron Green

Irish Communication Review

The purpose of this paper is to revisit C.P. Snow’s “Two Cultures” lecture in light of the cultural dominance of information technology. The crisis of communication in the information age, whether in fake news, political polarisation or science denial, has come about because both scientific and literary cultures, in seeking a world without entropy, have inadvertently stumbled upon a world without meaning. In order to explain how this has happened, the paper first explores Snow's challenge: to describe the second law of thermodynamics. The paper then provides a description of entropy that is neutral with regard to thermodynamics and information, …

Contact In The Unitary Fermi Gas Across The Superfluid Phase Transition, S. Jensen, Christopher N. Gilbreth, Y. Alhassid

All Faculty Scholarship for the College of the Sciences

A quantity known as the contact is a fundamental thermodynamic property of quantum many-body systems with short-range interactions. Determination of the temperature dependence of the contact for the unitary Fermi gas of infinite scattering length has been a major challenge, with different calculations yielding qualitatively different results. Here we use finite-temperature auxiliary-field quantum Monte Carlo (AFMC) methods on the lattice within the canonical ensemble to calculate the temperature dependence of the contact for the homogeneous spin-balanced unitary Fermi gas. We extrapolate to the continuum limit for 40, 66, and 114 particles, eliminating systematic errors due to finite-range effects. We observe …

Testing A Thermodynamic Approach To Collective Animal Behavior In Laboratory Fish Schools, Julia A. Giannini, James G. Puckett

Physics and Astronomy Faculty Publications

Collective behaviors displayed by groups of social animals are observed frequently in nature. Understanding and predicting the behavior of complex biological systems is dependent on developing effective descriptions and models. While collective animal systems are characteristically nonequilibrium, we can employ concepts from equilibrium statistical mechanics to motivate the measurement of material-like properties in laboratory animal aggregates. Here, we present results from a new set of experiments that utilize high speed footage of two-dimensional schooling events, particle tracking, and projected static and dynamic light fields to observe and control the behavior of negatively phototaxic fish schools (Hemigrammus bleheri). First, …

Amyloid Proteins And Fibrils Stability, Farbod Mahmoudinobar

Dissertations

Compared to globular proteins that have a stable native structure, intrinsically disordered peptides (IDP) sample an ensemble of structures without folding into a native conformation.One example of IDP is the amyloid-beta(Abeta) protein which is the main constituent of senile plaques in the brain of Alzheimer's patients.Understanding the process by which IDPs undergo structural changes to form oligomers that eventually aggregate into senile plaques/amyloid fibrils may significantly advance the development of novel therapeutic methods to treat neurodegenerative diseases, for which there is no cure to date. This dissertation has two main objectives. The first one is to investigate and identify structural …

Theoretical Investigations Of The Electronic, Magnetic, And Thermoelectric Properties Of Transition-Metal Based Compounds, Haleoot Edaan Raad

Graduate Theses and Dissertations

The electronic, magnetic, and thermoelectric properties of transition-metal based compounds were investigated by using the density functional theory and Boltzmann transport formalism. It was found that the Co-based Heusler compounds and InSe monochalcogenide are among the materials that may be used for future thermoelectric devices. Furthermore, the investigation showed that the quaternary Heusler compounds, such as, CoFeYGe, where Y is Ti or Cr, are half-metallic ferromagnetic materials with full electron spin polarization. The lattice thermal conductivity (κL) was found to decrease for these alloys as the temperature increases. The present investigation indicated that the phonon optical modes have a major …

Planck's And Callendar's Blackbody Radiation Formulas And Their Fitness To Experimental Data, Max Tran

Publications and Research

In this paper, we compare the blackbody radiation density formula obtained with classical physics by Hugh L Callendar and the formula obtained by Max Planck using quantization of energy. We use R and Maxima to analyze their fitness on coordinating experimental data and indicate some limitations with experiments in this area.

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 the legitimacy …

Thermodynamic Properties Of V, Cr, Mo, And Fe Metals And Their Binary Alloys, Taiwo Akande, Fadeke Matthew-Ojelabi, Gbenga Agunbiade, Ebenezer Babatope Faweya

Turkish Journal of Physics

The interactions between distinctive alloying elements have been scrutinized through atomistic investigation for essential material selection. The tight-binding model was applied to compute the thermodynamic properties of V, Cr, Mo, and Fe metals and their binary alloys. The calculated results agree with the accessible experiment in some cases, while some are closer in agreement with the experiment. The minimum formation enthalpies observed are -17.80, -15.20, -13.10, -11.50, and -0.90 eV for Cr-Mo, Cr-V, Fe-V, V-Fe, and Mo-Cr, respectively. The Cr-Mo alloy is the most stable of all the selected alloys with the least formation enthalpy. For the alloy structure, bcc …

A Network Theoretical Approach To Real-World Problems: Application Of The K-Core Algorithm To Various Systems, Kate Burleson-Lesser

Dissertations, Theses, and Capstone Projects

The study of complex networks is, at its core, an exploration of the mechanisms that control the world in which we live at every scale, from particles no bigger than a grain of sand and amino acids that comprise proteins, to social networks, ecosystems, and even countries. Indeed, we find that, regardless of the physical size of the network's components, we may apply principles of complex network theory, thermodynamics, and statistical mechanics to not only better understand these specific networks, but to formulate theories which may be applied to problems on a more general level. This thesis explores several networks …

The Effects Of Surface Pace In Baseball, Jason Farlow

Senior Theses

A baseball travels across different surfaces at different paces. The goal of this experiment is to find a percentage difference in speeds the ball will reflect off a given surface. The energy lost on the turf surface was far more significant than on dirt surface as the turf lost an average of 26% of its energy as compared to just 16% of the energy on dirt. In the Northwest conference, teams play on four turf-based infields and five dirt-based infields. The results of this study suggest that kinetic friction forces are more significant in reducing ball rebound speed than in …

Super Inflation Mechanism And Dark Energy From A Cosmological Entropy Perspective, Ali̇ İhsan Keski̇n

Turkish Journal of Physics

Various approaches are developed that provide a unification of the early inflationary epoch of the universe and dark energy (cosmic accelerating expansion case). In one respect, we express this unification in a universal thermodynamic framework within the context of $F\left( T,T_{G} \right)$ gravity, where $T$ represents the torsion invariant and $T_{G}$ is the teleparallel equivalent of the Gauss--Bonnet term. For a Friedmann-Robertson-Walker universe model bounded by the dynamical apparent horizon, we explore the generalized second law of gravitational thermodynamics (GSLT). Finally, we discuss the super inflation mechanism, the deceleration case (radiation and dust regions), and the late time cosmic acceleration …

Thermodynamics Of Cosmological Models With Generalized $G$ And $\Lambda $, M Saratchandra Singh, Sanasam Surendra Singh

Turkish Journal of Physics

Here we investigate spatially flat Friedmann-Robertson-Walker space-time models of the universe to study the thermodynamic behaviors in light of variables $G$ and $\Lambda $. A particular method to find the solutions of Einstein's field equations and mathematical expressions for temperature and entropy of the perfect fluid cosmological models is introduced by using both the equation of state and the assumption $G=G_{0} \,a^{n}$. It is observed that the phantom field of ($\omega

Nature Of Entropy In A Scalar-Tensor Theory Of Gravity, Onur Siğinç, Mustafa Salti, Hi̇lmi̇ Yanar, Oktay Aydoğdu

Turkish Journal of Physics

This work is devoted to studying the generalized nature of the entropy function in a specific form of the scalar-tensor-vector (STeVe) theory of gravity for the Friedmann-Lemaitre-Robertson-Walker (FLRW) spacetime in the state of thermal equilibrium. For this purpose, we define an equilibrium picture of thermodynamics by making use of a suitable set of the dark energy density and dark pressure descriptions, which defines an energy-momentum tensor obeying the local energy conservation law. Furthermore, we also discuss our results numerically in order to get additional implications.

Comment On "Roles Of Bulk Viscosity On Rayleigh-Taylor Instability: Non-Equilibrium Thermodynamics Due To Spatio-Temporal Pressure Fronts" Phys. Fluids 28, 094102 (2016), Robert L. Ash

Mechanical & Aerospace Engineering Faculty Publications

No abstract provided.

Second Law Of Gravitational Thermodynamics In The Locally Rotationally Symmetric Bianchi Type-Ii Universe, Murat Korunur

Turkish Journal of Physics

In this work, under the assumption that the universe is locally rotationally symmetric (LRS) Bianchi type-II and filled with anisotropic dark fluid (dark energy and dark radiation), we investigate whether the generalized second law of thermodynamics (GSLT) is still valid. We also consider another important condition for LRS Bianchi type-II spacetimes whereby the model expansion $\theta $ is proportional to the shear $\sigma $, which leads to $B=A^{n}$ (where n is a constant and A and B are the metric potentials). Based on this, we derive a general circumstance for the GSLT and find that its validity depends on the …

Student Understanding Of The Boltzmann Factor, Trevor I. Smith, Donald B. Mountcastle, John R. Thompson

Physics and Astronomy Faculty Scholarship

We present results of our investigation into student understanding of the physical significance and utility of the Boltzmann factor in several simple models. We identify various justifications, both correct and incorrect, that students use when answering written questions that require application of the Boltzmann factor. Results from written data as well as teaching interviews suggest that many students can neither recognize situations in which the Boltzmann factor is applicable nor articulate the physical significance of the Boltzmann factor as an expression for multiplicity, a fundamental quantity of statistical mechanics. The specific student difficulties seen in the written data led us …

Identifying Student Difficulties With Heat Engines, Entropy, And The Carnot Cycle, Trevor I. Smith, Warren M. Christensen, Donald B. Mountcastle, John R. Thompson

Physics and Astronomy Faculty Scholarship

We report on several specific student difficulties regarding the second law of thermodynamics in the context of heat engines within upper-division undergraduate thermal physics courses. Data come from ungraded written surveys, graded homework assignments, and videotaped classroom observations of tutorial activities. Written data show that students in these courses do not clearly articulate the connection between the Carnot cycle and the second law after lecture instruction. This result is consistent both within and across student populations. Observation data provide evidence for myriad difficulties related to entropy and heat engines, including students’ struggles in reasoning about situations that are physically impossible …

Identifying Student Difficulties With Entropy, Heat Engines, And The Carnot Cycle, Trevor I. Smith, Warren M. Christensen, Donald B. Mountcastle, John R. Thompson

Faculty Scholarship for the College of Science & Mathematics

We report on several specific student difficulties regarding the second law of thermodynamics in the context of heat engines within upper-division undergraduate thermal physics courses. Data come from ungraded written surveys, graded homework assignments, and videotaped classroom observations of tutorial activities. Written data show that students in these courses do not clearly articulate the connection between the Carnot cycle and the second law after lecture instruction. This result is consistent both within and across student populations. Observation data provide evidence for myriad difficulties related to entropy and heat engines, including students’ struggles in reasoning about situations that are physically impossible …

Investigation Of The Thermodynamic Properties Of The Oligomerization Domain Of Heterogeneous Nuclear Ribonucleoprotein C, John P. O'Brien Iii

Honors Theses

The heterogeneous nuclear ribonucleoprotein C (hnRNP C) performs a critical role in the processing of nascent pre-messenger ribonucleic acid (pre-mRNA) transcripts as they exit DNA polymerase II. As the pre-mRNA transcripts emerge from the polymerase complex, they are bound by hnRNP C only if its nucleotide (NT) chain is longer than a certain nucleotide length. If the chain is long enough and binding occurs, the nucleotide strand is exported and processed as mRNA, whereas if the length requirement is not met, the RNA sequence is directed along a pathway to become small nuclear RNA (snRNA). The functional form of hnRNP …