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26 public papers

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Year

2026

26 papers
exp-20260921-297ee9 Public since September 21, 2026

In this paper, we use multiple techniques to find the complete set of solutions to Pell and negative Pell equations. We prove the existence of a nontrivial solution to the former using Dirichlet's Approximation Theorem and then find all so…

exp-20260903-065691 Public since September 3, 2026

Sparse linear algebra is the study of linear systems Ax = b in which the matrix A contains overwhelmingly many zero entries. Such systems arise throughout applied mathematics and engineering from the discretization of partial differential…

exp-20260902-971b21 Public since September 2, 2026

The representations of the Symmetric Groups S_n carry a very rich combinatorial structure. In particular, their representations have connections to seemingly unrelated problems, including to symmetric polynomials and the theory of Young Ta…

Preprint
exp-20260831-3d34ce Public since September 1, 2026

This paper builds up and proves the Poincaré-Hopf Theorem for compact smooth manifolds. Beginning with the introduction of key concepts in differential topology, including smooth manifolds, coordinate charts, tangent spaces, and mappings, …

Preprint
exp-20260825-541097 Public since August 26, 2026

The symmetric groups are fundamental objects in abstract algebra, and for nearly every value of n, their automorphism groups are completely inner. The unique exception is the symmetric group S_6, which possesses a nontrivial outer autom…

exp-20260823-b8b540 Public since August 23, 2026

This paper gives an expository introduction to arithmetic progressions in Ramsey theory and additive combinatorics. We begin with the language of colorings, using small examples to illustrate how simple coloring rules can force surprisingl…

exp-20260820-872577 Public since August 20, 2026

In this paper, we will introduce Fourier Series through the Orthogonality Relations from which we consider Parseval's Theorem. Then, we wish to extend the concept of Fourier Series of aperiodic functions, specifically showing the Fourier T…

exp-20260820-567e07 Public since August 20, 2026

Firstly, we will introduce some preliminary theory about Newton Polygons while presenting some comments for their uses. Our main focus is analyzing the Newton Polgons of general functions, specifically power series, of which a few importan…

On Minimal Surfaces

Aleksei Lopatin

Preprint
exp-20260819-321582 Public since August 20, 2026

This paper introduces Minimal Surfaces through the Weingarten Map and the 1st and 2nd Fundamental forms. Then, we consider two examples of a minimal surface, the catenoid and helicoid, verifying that both are indeed minimal surfaces throug…

exp-20260810-06b084 Public since August 10, 2026

We investigate the geometric and combinatorial properties of polytope triangulations, focusing on their connections to Ehrhart positivity. The Ehrhart polynomial L(P,t) encodes the number of integer points in dilated copies of a polyt…

exp-20260809-4d0c94 Public since August 10, 2026

This paper describes the mathematical technique of calculus of variations starting with the derivation of key equations such as the Euler-Lagrange equation and the Beltrami Identity. These equations are then applied in the following scenar…

exp-20260808-719d7e Public since August 8, 2026

The Fundamental Theorem of Calculus, Green's theorem, the classical Stokes theorem, and the divergence theorem each relate differentiation on a region to integration on its boundary. This paper develops the language of smooth manifolds…

exp-20260807-cc7636 Public since August 7, 2026

Sidorenko's conjecture predicts that the homomorphism density of a bipartite graph H in a host graph G satisfies t_H(G) ≥ t_{K_2}(G)^|E(H)|. We introduce the conjecture through homomorphism densities, prove the finite-host inequality for P…

exp-20260807-9c0bc6 Public since August 7, 2026

In this paper we show that the chromatic function $P(G,t)$ is always a polynomial. We then ask a simple question: where does this polynomial equal zero? Tutte showed that two stretches of the real line, $(-\infty,0)$ and $(0,1)$, can never…

Preprint
exp-20260802-a7f367 Public since August 2, 2026

This paper primarily discusses the proof of the Mahler-Lech-Skolem through the uses of p-adic analysis in its connection to Strassman's Theorem and p-adic interpolation. As this theorem is so closely related to p-adic analysis, we make a b…

exp-20260720-e17a32 Public since July 20, 2026

Combinatorial game theory and coding theory appear to be completely separate fields at first glance. However, they share a profound connection through structures known as lexicographic codes, or lexicodes. First introduced by Conway and Sl…

exp-20260713-29a3e9 Public since July 13, 2026

Hyperbolic geometry is a non-Euclidean geometry where geodesics play the role of straight lines. It is characterised by a constant negative curvature. The idea was conceived when mathematicians tried to understand the parallel postulate. T…

exp-20260712-820308 Public since July 12, 2026

In statistics, signal processing, and machine learning, the information we want from a matrix is carried by its singular values and singular vectors, yet the matrix we observe is almost never the one we want: it has been corrupted by measu…

Preprint
exp-20260629-089b18 Public since June 29, 2026

A tropical curve is a graph with specified edge lengths, some of which may be infinite. Various facts and attributes about algebraic curves have analogs for tropical curves. In this article, we focus on divisors and linear series, and prov…

exp-20260629-af4051 Public since June 29, 2026

This paper tries to create an intuition behind the proof of the fundamental theorem–Weierstrass approximation theorem–which will be shown using Bernstein polyno- mials and its generalization beyond polynomials–the Stone-Weierstrass theor…

Preprint
exp-20260629-82d131 Public since June 29, 2026

An essay that presents a first-principles approach to eigenvalue dynamics of the wave equation applied in context of timpani tuning.

Preprint
exp-20260628-a87bee Public since June 28, 2026

This expository paper explains tessellations of the hyperbolic plane from a differential-geometric viewpoint. We review the upper half-plane (H) and Poincaré disk (D) models and the Cayley transform linking them. We prove that orientation-…

exp-20260628-da4ff9 Public since June 28, 2026

We validate an inverse-drag estimation pipeline for finned spherical projectiles and, within this experimental regime, detect a robust non-monotonic effective-drag anomaly near L≈1.00. The pipeline pairs a custom fourth-order Runge–Kutta t…

exp-20260624-d94acb Public since June 24, 2026

In this paper, we begin with the concept of a projection in the familiar vector space R^n, and then extend it to an arbitrary inner product space. This foundational idea enables us to compute a line of best fit, approximate functions using…

Preprint
exp-20260624-a60dbd Public since June 24, 2026

In this paper, we explore matroids, which generalize properties of linear independence of vectors and cycles in graphs. We investigate properties and operations on matroids, then we look at how we can represent matroids using matrices.

exp-20260623-9d9bca Public since June 23, 2026

In this article, we show that locally compact groups have invariant measures, also known as Haar measures. We also show that such measures are unique up to scaling.