Mathematics Commons^™

Normal Matrices, Fuzhen Zhang

Mathematics Colloquium Series

Normal matrices form a central class in matrix analysis, including Hermitian, skew-Hermitian, and unitary, positive semidefinite, permutation matrices and so on. This presentation surveys fundamental properties of normal matrices, including spectral characterization, unitary diagonalization, and trace (in)equality through majorization. It highlights equivalent conditions for normality, with discussions extending to matrix exponentials and polynomials. Examples and counterexamples are provided to clarify certain subtle points about matrix normality. The talk is based on a recent paper published in JMC (joint work with Y.-J. Hu)

Emergent Storylines That Influence Positions And Mathematical Status In Collaborative Small-Group Proof Activity, Brittney M. Ellis, Tenchita Alzaga Elizondo

School of Mathematical & Statistical Sciences Faculty Publications

In this paper, we used positioning theory to examine storylines that emerged in students’ discourse as they collaborated on a proof construction task. We purposefully selected a case of group work from an inquiry-oriented introduction to proof course as prior analyses showed it was highly collaborative (Alzaga Elizondo, 2022), yet power dynamics seemed unbalanced. We hypothesized that positioning theory could provide a useful lens to interrogate such power dynamics. Through this analysis, we identified several implicit storylines that influenced the interaction related to the nature of proofs, the nature of mathematics, writing proofs, the role of an external authority, …

Modeling Bitcoin Dynamics Using Differential Equations, Boone M. Fleenor

Departmental Honors & Graduate Capstone Projects

In this thesis, we develop and analyze two nonlinear systems of ordinary differential equations to model Bitcoin price dynamics. Analytical techniques are used to obtain exact or approximate solutions where possible. Then, numerical simulations using a fourth-order Runge–Kutta method are employed to explore system behavior beyond analytically tractable regimes. Finally, model outputs are compared to historical Bitcoin price data using normalized and resampled time series. These results suggest that deterministic models can provide meaningful insight into the structural behavior of Bitcoin markets, while highlighting the need for stochastic or time-dependent extensions for more realistic modeling.

Fourier Analysis Of Electronic Synthesizer Waveforms, Jiayan Ling, Jack W. Maseberg

SACAD: Scholarly Activities

We compute Fourier series coefficients for some standard electronic synthesizer waveforms and provide plots of our results.

Unique Combinations Of Packing Integer Squares, Keith M. Dreiling, Austin Leanna, William Mooney

SACAD: Scholarly Activities

This research investigates a function, informally named WAK(x), that describes the number of ways to divide an integer square into integer subsquares counting only the list of parts. Previous research has shown values up to 28, though finding these values is computationally complex and requires a long runtime using computer algorithms. We attempt to find patterns in the values and many aspects of the values, hoping to find a general solution. We are unsure if a solution exists, but we have ideas for how to move forward in finding a solution.

Mathematical Modeling, Analysis And Numerical Simulation Of Air Quality Using The Advection-Diffusion-Reaction Equation, Md Timorul Islam

Math Theses

In this thesis, we study an air quality model by using a nonlinear one-dimensional advection-diffusion-reaction system of partial differential equations for NO-NO2-O3 chemical cycle. The model incorporates advection, diffusion, chemical reactions, and source terms, and is formulated based on standard atmospheric chemistry.

We first develop numerical methods to approximate the solutions of the governing equations. Both explicit and implicit finite difference schemes are considered, and the implicit scheme provides approximations without any restrictions on the stability.

The model is then nondimensionalized to identify key parameter combinations governing the system. This leads us to a regime in which the transport and …

Counting Hamiltonian Cycles In Quartic Circulant Graphs, Allison Hilliard

Seaver College Research And Scholarly Achievement Symposium

We consider the problem of counting Hamiltonian cycles in circulant graphs $C^K_n$ where $n$ is the number of vertices and $K$ is a set containing elements that correspond to the allowed edges in the circulant graphs. After sorting the cycles by a topological invariant called the winding number, we use a modified transfer matrix method to convert local data into global structures. The result is a generating function that counts the number of Hamiltonian cycles in a circulant graph with $n$ vertices. The results for $K=\{1,2\}$ and $K=\{1,3\}$ have been found by previous authors. We focus on the case where …

Tipping Points In Crayfish Management: Exploring Population Dynamics With The Bifurcations Activity In Slopes, Evan Inrig, Benjamin Lucas

Seaver College Research And Scholarly Achievement Symposium

Slopes is an interactive environment for exploring numerical methods and graphical solutions to ordinary differential equations. The app launched with five activities for exploration: slopefields, phase planes, oscillations, solutions to systems, and numerical methods for approximation. Bifurcations is a new sixth activity that we designed to investigate changes in the long term behavior of solutions to autonomous differential equations. This activity displays a slopefield and implements the ability to add solutions, but also introduces two new views that show how varying a single parameter impacts the values and stability of equilibrium solutions. We demonstrate the value of the new bifurcations …

Irreversible K-Threshold Dynamics On Corona And Base-B Corona Product Graphs, Eric J. Moon, Soumya Bhoumik, Paul Flesher

SACAD: Scholarly Activities

This poster studies the irreversible k-threshold process on corona-type graph products, where a vertex becomes colored once at least k of its neighbors are colored and then remains colored permanently. We focus on corona, double corona, and base-b corona product graphs built from cycles and complete graphs, with particular attention to how graph structure affects complete activation from a minimum seed set.

A generalized reduction lemma is used to relate threshold dynamics on layered corona graphs to smaller residual graphs, yielding explicit formulas for the irreversible k-threshold conversion number on both corona and double corona families. The …

From Counting To Advanced Math: How Five Simple Axioms Shape The Mathematical Landscape, Joy Skaggs

ATU Scholars Symposium

In the late nineteenth and early twentieth centuries, mathematics faced a foundational crisis: Greog Cantor’s set theory led to an interesting self-referencing paradox in math and questions about the logical consistency of mathematics. From this crisis, two opposing viewpoints emerged: the Formalists and the Intuitionists. The Formalists praised Cantor’s work as a way to place math on a secure logical foundation, ensuring the discipline’s purity, however the Intuitionists despised Cantor’s work and heralded Cantor as a charlatan and corrupter of the youth. The leader of the Formalists, David Hilbert, proposed a formal system of rigorous proofs to build a complete …

Extremal Connectivity In Graphs And Matroids, Yiwei Ge

LSU Doctoral Dissertations

Connectivity is a central theme in both graph theory and matroid theory. This dissertation investigates extremal connectivity in graphs and matroids, with emphasis on unavoidable structures and minimal connectivity phenomena.

Chapter 2 introduces cycle-contraction minors of graphs and investigates their structural properties. We establish a connection between cc-minors and induced subgraphs via graph duality. The main result gives an unavoidable-families characterization for cc-minors of sufficiently large loopless $2$-connected graphs.

Chapter 3 studies super-minimally $3$-connected graphs, namely $3$-connected graphs that have no proper $3$-connected subgraphs. We establish extremal bounds on structural parameters of these graphs, including the minimum number of degree-$3$ …

Ideals And Lattices In Number Fields, Sarah Ali Saeed Alyammahi

Thesis/ Dissertation Defenses

This thesis investigates algebraic number fields and their rings of integers, which generalize the ring of integers Z in Q. The study focuses on ideals, units, and ideal class groups, which describe the arithmetic structure of number fields and the failure of unique factorization. Key invariants such as the norm, trace, and discriminant are developed and applied, with particular emphasis on quadratic number fields and classical examples such as the Gaussian and Eisenstein integers. Some explicit computations of ideal class groups are carried out. The thesis also explores connections with lattice theory by interpreting rings of integers as lattices and …

On Topological And Algebraic K-Theories, Amar Yasser Aldakheel

Thesis/ Dissertation Defenses

This thesis explores topological K-theory, a powerful framework for studying invariants of topological spaces via algebraic structures. We investigate the construction of K-groups, with particular emphasis on the categorical formulation. The exposition is structured pedagogically, with careful development of the main concepts supported by detailed proofs and examples. The categories of vector bundles and projective modules are thoroughly defined and investigated. A central result studied in this thesis is the Serre–Swan theorem, which provides a bridge between the algebraic context of projective modules and the geometric context of vector bundles, enabling the use of algebraic techniques to solve geometric problems, …

A 4-Dimensional Rubik’S Cube You Can Hold: How It’S Possible And The Math Behind It, Eric J. Moon

SACAD: Scholarly Activities

This poster examines the physical 2x2x2x2, a hand-held realization of a 4-dimensional Rubik’s Cube invented by Melinda Green. Unlike most higher-dimensional twisty puzzles, which exist only as software simulations, this puzzle provides a physical model for exploring 4-dimensional rotation, symmetry, and solving methods. The poster introduces the structure of the puzzle, its canonical move system, and several algebraic ideas that help explain how scrambling and solving work.

From a mathematical perspective, the puzzle can be studied using group actions, commutators, conjugation, and combinatorial counting. In particular, the number of reachable states depends on corner permutations, corner orientations, parity restrictions, twist …

Circuits And Enumeration Problems For Matroids, Christine H. Cho

LSU Doctoral Dissertations

This dissertation is a collection of work concerning the structure and enumeration of circuits and other distinguished sets in a matroid. The Tutte polynomial, recognized as the universal deletion-contraction invariant in matroid and graph theory, is a natural starting point when considering enumeration problems for matroids. The main result in Chapter 2 generalizes a theorem of Dean Lucas concerning the Tutte polynomial and its behavior under rank-preserving weak maps. This generalization provides an avenue for comparing the numbers of circuits, bases, rank-k flats, and hyperplanes of a matroid containing an element given two distinct, yet related, elements.

Chapter 3 addresses …

Instructors' Lived Experiences Of Using Authentic Assessments In College Calculus Courses Across The United States: A Phenomenological Study, Christy Hart Kains

Doctoral Dissertations and Projects

The purpose of this transcendental phenomenological study was to describe the lived experiences of instructors with authentic assessments in college calculus courses across the United States. The theory guiding this study was Astin’s student involvement theory, which provided a framework to study the involvement of students in higher education. The central research question for this study was: What are the lived experiences of instructors who utilize authentic assessments in college calculus courses across the United States? This study used a qualitative design following the transcendental phenomenological approach of Moustakas. The sample included 12 instructors from two-year and four-year colleges in …

Local-Nonlocal Dispersal, Behavioral Responses, And Intervention Strategies In Infectious Disease And Addiction Dynamics, Ghilmana Sarmad

Thesis/ Dissertation Defenses

This dissertation explores how epidemiological and behavioral processes interact across spatial and temporal scales to shape the dynamics of infectious diseases and addiction. Bringing together mathematical rigor and biological realism, it develops and analyzes a series of nonlinear models that capture the effects of spatial heterogeneity, mobility patterns, behavioral adaptation, and intervention strategies. Using tools from semigroup theory, functional analysis, stability analysis, and numerical simulation, the study provides a unified framework for understanding how awareness programs, fear-driven protection, vaccination, and social reinforcement influence transmission thresholds, persistence, and long-term population outcomes.

awareness-based interventions, where a basic reproduction number is derived and …

Indexed Concatenation (I-Cat): A Method For Representing And Operating On Repeating Numbers*, Abigail Touma, Isaac Wolford

Campus Research Month

Our research presents Indexed Concatenation (I-Cat) notation as a structured way to represent numbers with repeating patterns, including both decimals and whole numbers. Instead of treating expressions like 0.333... or 735735735 as unstructured expansions, they are rewritten as compact repeating objects called I-Cats. The presentation demonstrates how arithmetic operations, including addition and multiplication, can be performed using hypothesized rules such as the "U = M/C" method, unpacking, and carry propagation. Examples progress from simple conversions and multiplication by integers to the multiplication of two I-Cats. A live visual demonstration will show how standard numerics transform into I-Cat form and how …

Sex-Specific Differences In Lung Mitochondrial Function And Injury In Rats Exposed To Hyperoxia, Taheri Pardis, Abraham G. Taye, Devanshi D. Dave, Elizabeth R. Jacobs, Guru Prasad Sharma, Anne V. Clough, Ranjan K. Dash, Said H. Audi

Mathematical and Statistical Science Faculty Research and Publications

Hyperoxia is both an essential therapy and a contributor to lung injury in acute respiratory distress syndrome. We hypothesized that adult female rats are relatively protected from hyperoxia-induced acute lung injury (HALI) compared with males and that this protection is associated with sex-dependent differences in lung mitochondrial bioenergetics and H₂O₂ production. Adult rats were exposed to room air (normoxia) or hyperoxia (>95% O₂) for up to 60 h. Lung injury was assessed by pleural effusion, lung wet weight, pulmonary vascular filtration coefficient (K_f), histologic injury scores, and cleaved caspase-3 (CC3) staining. …

Variational Data Assimilation With Steepest Descent Method For Coupled Time-Dependent Stokes-Darcy Model With Bjsj Interface Condition, Yafang Hei

Miners Solving for Tomorrow Research Conference

Variational data assimilation (VDA) determines the initial condition of a dynamical system by minimizing the mismatch between model predictions and observed data. This work studies VDA for the time-dependent Stokes–Darcy system with the BJSJ interface condition. The problem is formulated as a PDE-constrained optimization problem, and the first-order optimality system is derived using the Gâteaux derivative and adjoint variables. A steepest descent method is applied for efficient computation. Spatial and temporal discretizations are carried out using the finite element method and backward Euler scheme, respectively. Numerical results confirm accuracy and convergence.