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Physics Preprint PDF DOI

Order by disorder up to arbitrarily high temperature

Ravish Mehta · 2026

We prove that a class of classical lattice models on $\mathbb{Z}^d$ ($d \geq 2$) with on-site space $\mathbb{N}_0$ exhibits long-range checkerboard order at sufficiently high temperature. The model ha…

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Mathematics Preprint PDF DOI

Existence and maximal corank of simple $Z_p$-invariant germs

Ivan Proskurnin · 2026

In this paper we improve the previously achieved upper bound on the corank of an equivariantly stable singularity for a group of prime order. We also prove that the maximal corank of a simple $\mathbb…

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AI & Data Science Preprint PDF DOI

Online learning with Erd\H{o}s-R\'enyi side-observation graphs

Tomas Kocak, Gergely Neu, Michal Valko · 2026

We consider adversarial multi-armed bandit problems where the learner is allowed to observe losses of a number of arms beside the arm that it actually chose. We study the case where all non-chosen arm…

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Economics & Finance Preprint PDF DOI

Property, Interest, and Money: Is Heinsohn and Steiger's Property Premium a Determinant of Interest?

Eric Hillebrand · 2026

Heinsohn and Steiger's "Eigentum, Zins und Geld" (1996) proposes the property premium as the foundational determinant of interest, replacing time preference. This paper examines whether the replacemen…

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Mathematics Preprint PDF DOI

Unbounded logarithmic limsup in Erd\H{o}s problem 684

Ji Ho Bae · 2026

For $0\le k\le n$, write $\binom nk=uv$ where the primes dividing $u$ are at most $k$ and the primes dividing $v$ exceed $k$, and let $f(n)$ be the least $k$ with $u>n^2$; Erd\H{o}s problem 684 asks f…

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Mathematics Preprint PDF DOI

Integral Perverse Obstructions for Normal Surface Singularities: Resolution Determinants and Monodromy

Abdul Rahman · 2026

For a germ $(X,0)$ of a normal complex analytic surface, let $E:=H^0({}^p_+IC_X\mathbb Z)_0$, where ${}^pIC_X\mathbb Z$ and ${}^p_+IC_X\mathbb Z$ denote the ordinary and dual middle-perversity interse…

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Mathematics Preprint PDF DOI

3-Designs from $\mathrm{GL}_2(\mathbb{F}_q)$-Invariant Subspaces of $\mathbb F_q[X,Y]_k$

Huawei Wu, Lewen Wang, Sihuang Hu · 2026

We present a uniform framework for constructing $3$-designs from $\mathrm{GL}_2(\mathbb F_q)$-invariant subspaces of $\mathbb F_q[X,Y]_k$, the space of homogeneous polynomials of degree $k$. Given suc…

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Mathematics Preprint PDF DOI

A resolution of Erd\H{o}s Problem #190 via Erd\H{o}s-Lov\'asz, BCT, and Baker-Harman-Pintz

Ji Ho Bae · 2026

Let H(k) be the smallest N such that every finite coloring of [N] contains a monochromatic or rainbow k-term arithmetic progression. Erd\H{o}s and Graham asked whether $H(k)^{1/k}/k \to \infty$ (Probl…

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Mathematics Preprint PDF DOI

Combinatorial Geometry of Erd\H{o}s--Szekeres Type Problems: SAT/ASP Modeling and Linear Subreduction

Vitalii Koshelev, Alexey Koshka · 2026

This paper investigates several classical and novel variations of the Erd\H{o}s--Szekeres problem, including multicolored point sets, convex hexagons with a given number of interior points, and polygo…

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Mathematics Preprint PDF DOI

Explicit density computations for certain sets of primes in Lucas sequences

Joaquim Cera Da Conceicao · 2026

Let $U$ be a Lucas sequence, $p$ be prime, and $\rho_U(p)$ be the rank of appearance of $p$ in $U$. We derive closed-form formulas for the Dirichlet density of primes $p$ for which $d\mid \rho_U(p)$, …

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Mathematics Preprint PDF DOI

Counting sunflowers in hypergraphs with bounded matching number and Erd\H{o}s Matching Conjecture in the $(t,k)$-norm

Junpeng Zhou, Xiying Yuan · 2026

It is well known that Erd\H{o}s Matching Conjecture concerns the maximum number of hyperedges in an $r$-uniform hypergraph with bounded matching number. As a generalization, it is natural to ask for t…

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Computer Science Preprint PDF DOI

Mismatch Capacity under Stochastic Decoding

Francesc Molina, Albert Guillen i Fabregas · 2026

This manuscript investigates channel capacity under mismatched stochastic likelihood decoding. We derive Feinstein- and Verd\'u-Han-style bounds on the error probability coded communication. These are…

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Mathematics Preprint PDF DOI

Sophie Germain Primes and the Totient of Fibonacci Numbers

Aradhya Goel (Indian Institute of Technology, Kanpur) · 2026

We study the set $S(q)$ of residue classes $r$ modulo the Pisano period $\pi(q)$ for which $q \mid \varphi(F_m)$ for every $m \equiv r \pmod{\pi(q)}$. We prove that if $q$ is a Sophie Germain prime an…

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Mathematics Preprint PDF DOI

Forbidden subgraphs in divisor graphs and an Erd\H{o}s divisibility problem

Damek Davis · 2026

Erd\H{o}s asked for the largest size $f(n)$ of a subset of $\{1,\dots,n\}$ with no element dividing two others. We show that $f(n)=c_2\,n+o(n)$ for an effectively computable constant $c_2$, and moreov…

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Physics Preprint PDF DOI

Sachs Equations and Plane Waves VI: Penrose Limits

Jonathan Holland, George Sparling · 2026

We prove that the Penrose limit of a Lorentzian metric along an affinely parametrized null geodesic is intrinsic, but intrinsic on a weighted associated-graded model determined by the null filtration …

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Mathematics Preprint PDF DOI

Ramsey-finiteness for graph pairs: A complete solution to the Burr-Erd\H{o}s-Faudree-Schelp conjectures

Yaping Mao · 2026

For finite graphs $G$ and $H$, let $\RR(G,H)$ denote the isomorphism classes of Ramsey-minimal graphs for $(G,H)$. We prove two 1981 conjectures of Burr, Erd\H{o}s, Faudree, Rousseau, and Schelp: Rams…

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AI & Data Science Preprint PDF DOI

Conditional Evidence Reconstruction and Decomposition for Interpretable Multimodal Diagnosis

Shaowen Wan, Yanjun Lv, Lu Zhang, Dajiang Zhu, Bharat Biswal, Tianming Liu, Xiaobo Li, Lin Zhao · 2026

Neurobiological and neurodegenerative diseases are inherently multifactorial, arising from coupled influences spanning genetic susceptibility, brain alterations, and environmental and behavioral facto…

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Physics Preprint PDF DOI

Supersymmetry, Supergravity and Non--Perturbative Dynamics of Gauge Theories

Tetiana Obikhod · 2026

We present a review of supersymmetry, supergravity, and the non-perturbative dynamics of gauge theories, tracing a path from the supersymmetry algebra to moduli stabilisation and de~Sitter vacua in st…

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Computer Science Preprint PDF DOI

You can just review things: A digital ethnography of informal peer review

Jay Patel, Joel Chan · 2026

Across scholarly communities, manuscripts face similar evaluative rituals: editors invite experts to privately assess submissions through formal peer reviews. This closed, loosely structured, and publ…

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Mathematics Preprint PDF DOI

The Erd\H{o}s-Faudree Problems and the Isolate-Free Core

Yaping Mao · 2026

In 1981, Erd\H{o}s and Faudree asked whether there exists an infinite family of graphs $G_N$ on $N$ vertices with $\Delta(G_N)<N-1$ and $\sri(G_N)=1$, and whether every family with $|V(G_N)|=N$ and $\…

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