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Showing 736 results for "matej hoffmann" in Mathematics
Mathematics Preprint PDF DOI

A half-space theorem for nonlocal minimal surfaces

Matteo Cozzi, Jack Thompson ยท 2026

We establish a half-space theorem \`a la Hoffman and Meeks for nonlocal minimal surfaces. Differently from the classical case, our result holds in every dimension.โ€ฆ

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Mathematics Preprint PDF DOI

On a conjecture of distance spectral extremal problems

Hongzhang Chen, Jianxi Li, Yongtao Li ยท 2026

Brualdi and Hoffman proposed a well-known problem of determining the graph with maximum adjacency spectral radius among all graphs with given size $m$. Early work by Friedland and Stanley addressed soโ€ฆ

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Mathematics Preprint PDF DOI

On rates of convergence for sample average approximations without smoothness

Hien Duy Nguyen, Jacob Westerhout, Xin Guo ยท 2026

Sample average approximation (SAA) replaces an intractable expected objective by an empirical average and is a basic device of modern stochastic optimization. We develop a rate theory for optimal valuโ€ฆ

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Mathematics Preprint PDF DOI

Improving the Even-Size Threshold in Spectral Extrema for $H(4,3)$-Free Graphs

Shreyhaan Sarkar ยท 2026

For the fixed-size Brualdi--Hoffman--Turan problem forbidding the fish graph $H(4,3)$, Zheng and Zhang proved that every $H(4,3)$-free graph of even size $m \ge 38$ without isolated vertices satisfiesโ€ฆ

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Mathematics Preprint PDF DOI

Algebraic Graph Theory

M Reza Salarian ยท 2026

This note provides an introduction to selected topics in algebraic graph theory, including strongly regular graphs, Steiner systems, and automorphism groups. We describe constructions and properties oโ€ฆ

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Mathematics Preprint PDF DOI

Trajectory-Restricted Optimization Conditions and Geometry-Aware Linear Convergence

Faris Chaudhry, Anthea Monod, Keisuke Yano ยท 2026

Linear convergence of first-order methods is typically characterized by global optimization conditions whose constants reflect worst-case geometry of the ambient space. In high-dimensional or structurโ€ฆ

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Mathematics Preprint PDF DOI

A criterion for Tits alternative on the centralizer of a matrix

Adem Zeghib ยท 2026

We give a necessary and sufficient condition on a matrix for its centralizer in $\sf{GL}(n,\mathbb{Z})$ to be polycyclic, or equivalently in this case, not to contain a non-abelian free subgroup. We gโ€ฆ

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Mathematics Preprint PDF DOI

Almost all graphs have no cospectral mates with height relative small to its order

Da Zhao ยท 2026

The main result of this paper shows that almost all graphs of order $n$ have no cospectral mates with height $o(( n / \ln n)^{1/10})$, improving an earlier result on cospectral mates with fixed level โ€ฆ

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Mathematics Preprint PDF DOI

The Bollob\'{a}s--Nikiforov Conjecture for Complete Multipartite Graphs and Dense $K_4$-Free Graphs

Piero Giacomelli ยท 2026

The Bollob\'as--Nikiforov conjecture asserts that for any graph $G \neq K_n$ with $m$ edges and clique number $\omega(G)$, \[ \lambda_1^2(G) + \lambda_2^2(G) \;\leq\; 2\!\left(1 - \frac{1}{\omegโ€ฆ

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Mathematics Preprint PDF DOI

Spectral bounds for the independence number of graphs and even uniform hypergraphs

Xinyu Hu, Jiang Zhou, Changjiang Bu ยท 2026

In this paper, we give spectral upper bounds for the independence number of even uniform hypergraphs and graphs, extend the Hoffman bound to even uniform hypergraphs, and give a simple spectral conditโ€ฆ

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Mathematics Preprint PDF DOI

Hoffman colorability of graphs with smallest eigenvalue at least -2

Bart De Bruyn, Thijs van Veluw ยท 2026

In accordance with the Cameron-Goethals-Seidel-Shult Classification Theorem, we extend the characterization of Hoffman colorability of line graphs from (Abiad, Bosma, Van Veluw, 2025) to all connectedโ€ฆ

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Mathematics Preprint PDF DOI

Another proofs of Zagier's formula for multiple zeta values and Murakami's formula for multiple $t$-values

Jinmin Yu, Shaofang Hong ยท 2026

Let $l\ge 1$ be an integer. For any multiple index $\mathbf{s}=(s_1,s_2,\cdots,s_l)\in\mathbb{Z}_{\geq 1}^l$ with $s_l>1$, the multiple zeta value (MZV for short) is defined by \begin{align*} \zeta(s_โ€ฆ

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Mathematics Preprint PDF DOI

Are sparse graphs typically determined by their spectrum?

Nils Van de Berg, Alexander Van Werde ยท 2026

We investigate whether it is typical for a sparse graph to be uniquely characterized by its adjacency spectrum up to isomorphism. Our first result shows that the giant component of an Erd\H{o}s-R\'enyโ€ฆ

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Mathematics Preprint PDF DOI

Proofs of Lupu's conjectures for multiple zeta values and multiple $t$-values

Wenzhong Lei, Jinmin Yu, Shaofang Hong ยท 2026

Let $r\ge 1$ be an integer. For any multiple index $\mathbf{s}=(s_1,s_2,\cdots,s_r) \in\mathbb{Z}_{\geq 1}^r$ with $s_r>1$, the multiple zeta value (MZV for short) is defined by \begin{align*} \zeta(sโ€ฆ

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Mathematics Preprint PDF DOI

Symmetry Results for Cyclotomic Multiple Hurwitz Zeta Values via Contour Integrals

Ce Xu ยท 2026

This paper provides a systematic study of symmetry properties for cyclotomic multiple Hurwitz zeta values with multiple variables and parameters by applying the methods of contour integration and the โ€ฆ

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Mathematics Preprint PDF DOI

Maximally probable tree topologies with $r$-furcation

Emily H. Dickey, Noah A. Rosenberg ยท 2026

For a specific rooted labeled tree topology, a labeled history is a sequence of branchings that give rise to that labeled topology as it unfolds over time. Here, for $r$-furcating trees, we use a connโ€ฆ

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Mathematics Preprint PDF DOI

Spectral Theory for Borel PMP Graphs

Cecelia Higgins, Pieter Spaas, Alexander Tenenbaum ยท 2026

We initiate a systematic study of spectral theory for bounded-degree Borel pmp graphs. Specifically, we study spectral properties of the associated adjacency and Laplacian operators. We start with proโ€ฆ

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Mathematics Preprint PDF DOI

Half-space type theorems for a class of weighted minimal surfaces in $\mathbb{R}^{3}$

A. L. Martinez-Trivino, J. P. dos Santos, G. Tinaglia ยท 2026

We establish half-space type results for a class of height-dependent weighted minimal surfaces in $\mathbb{R}^3$, namely critical points of a weighted area functional whose weight depends on the heighโ€ฆ

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Mathematics Preprint PDF DOI

On the number of generalized cospectral mates of graphs

Muhammad Raza, Obaid Ullah Ahmad, Mudassir Shabbir, Waseem Abbas ยท 2026

This paper establishes an upper bound on the number of generalized cospectral mates of simple graphs, where the generalized spectrum consists of the spectrum of a graph and its complement. Moving beyoโ€ฆ

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Mathematics Preprint PDF DOI

Explosivity in 1-d Activated Random Walk

Nicolas Forien, Christopher Hoffman, Tobias Johnson, Josh Meisel, Jacob Richey, Leonardo T. Rolla ยท 2026

We show that Activated Random Walk on $\mathbb{Z}$ is explosive above criticality. That is, activating a single particle in a supercritical state of sleeping particles triggers an infinite avalanche oโ€ฆ

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