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Physics Preprint PDF DOI

New gravitational-wave templates for metastable cosmic strings: Loop breaking versus network collapse

Doa Hashemi Asl, Kai Schmitz ยท 2026

Metastable cosmic strings are a common prediction of grand unified theories and act as a source of a gravitational-wave background (GWB) that can explain the 2023 pulsar timing array (PTA) signal. In โ€ฆ

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Computer Science Preprint PDF DOI

Succinct Graph Representations and Algorithmic Applications

Ahammed Ullah, Alex Pothen ยท 2026

We propose new graph representations that exploit dense local structure to improve time and space simultaneously. Given an undirected graph $G$, we define a dual clique cover (DCC) representation of $โ€ฆ

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Physics Preprint PDF DOI

Giant Spin Magnetization from Quantum Geometry in Altermagnets

Neelanjan Chakraborti, Sudeep Kumar Ghosh, Snehasish Nandy ยท 2026

Altermagnets host spin-split band structures while exhibiting vanishing equilibrium spin magnetization, making field-induced responses a direct probe of their quantum geometry. A central question, in โ€ฆ

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Physics Preprint PDF DOI

g-tensor Optimization in Ge/SiGe Quantum Dots

Aram Shojaei, Edmondo Valvo, Maximilian Rimbach-Russ, Eliska Greplova, Ana Silva ยท 2026

Planar germanium heterostructures hosting hole-spin qubits are among the leading platforms for scalable semiconductor-based quantum computing. Yet, device performance is hindered by significant quantuโ€ฆ

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Mathematics Preprint PDF DOI

Hypergraph independence bounds: from maximum degree to average degree

Jing Yu, Junchi Zhang ยท 2026

We prove a transfer theorem for hereditary classes of $(r+1)$-uniform hypergraphs. Let $\mathcal G$ be such a class, and for $H\in\mathcal G$ write $\Delta(H)$ and $d(H)$ for the maximum degree and avโ€ฆ

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Mathematics Preprint PDF DOI

Extremal graphs for average size of maximal matchings in bicyclic graphs

Kai Zhang ยท 2026

For a graph \(G\), let $avm(G)$ denote the average size of its maximal matchings. This parameter was introduced by Engbers and Erey in the study of extremal problems for maximal matchings, and they asโ€ฆ

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Mathematics Preprint PDF DOI

Classification results of Liouville equations and rigidity of Riemannian surfaces

Qianzhong Ou ยท 2026

We study the Liouville equation $\triangle u+e^{2u} =0$ in a Riemannian surface $(M, g)$ with nonnegative $Ricci$ curvature. Under some asymptotic lower bound assumptions, we classify all the solutiโ€ฆ

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Computer Science Preprint PDF DOI

Simpler and Improved Replacement Path Coverings

Davide Bilo, Shiri Chechik, Keerti Choudhary, Sarel Cohen, Martin Schirneck ยท 2026

An important tool in the design of fault-tolerant graph data structures are $(L,f)$-replacement path coverings (RPCs). An RPC is a family $\mathcal{G}$ of subgraphs of a given graph $G$ such that, forโ€ฆ

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Physics Preprint PDF DOI

Rotation-Induced Pressure Anisotropy in Newtonian White Dwarfs: Sequences and Applicability Criteria

Aray Muratkhan, Saken Toktarbay, Hernando Quevedo ยท 2026

We introduce a fast, one-dimensional Newtonian {reduced model} to capture uniform rotation in cold white dwarfs, encoding centrifugal support as an effective pressure anisotropy. Using $\Delta_{\rm roโ€ฆ

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Mathematics Preprint PDF DOI

Stein's square function associated with the Bochner-Riesz means on M\'etivier groups and its applications

Joydwip Singh ยท 2026

In this paper, we study the $L^p$-boundedness of Stein's square function $\mathfrak{S}^{\alpha}(\mathcal{L})$ associated with the sub-Laplacian $\mathcal{L}$ on M\'etivier group $G$. A key aspect of oโ€ฆ

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Mathematics Preprint PDF DOI

Sufficient conditions for spanning $k$-trees in tough graphs

Caili Jia, Yong Lu ยท 2026

The toughness of a graph $G$, denoted by $\tau(G)$, is defined by $\tau(G)=$min $\{\frac{|S|}{c(G-S)}:S\subseteq V(G)$ and $c(G-S)\geq2\}$. A graph $G$ is said to be $\tau$-tough if $\tau(G)\geq \tau$โ€ฆ

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Physics Preprint PDF DOI

A New Perspective on Galactic Evolution: Studying the Outskirts of the Abell S1063 Galaxy Cluster

L. Pecoraro, A. Mercurio, M.Annunziatella, M. D'Addona, R. Ragusa, G. Angora, M. Girardi, G. Granata, C. Grillo, L. Limatola, P. Rosati, P. Bergamini, G. Caminha, F. Getman, A. Grado, M. Meneghetti, E. Vanzella ยท 2026

Galaxy physical properties are influenced by their environments, but the processes responsible for mass and environmental quenching and structural transformations remain debated. Galaxy clusters are iโ€ฆ

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Biology & Life Sciences Preprint PDF DOI

The Lifetime Cardiac-Cycle Invariant in Endothermic Vertebrates: A 230-Species Comparative Dataset, Statistical Validation, and Explicit Falsifiability Criteria

Mesfin Taye ยท 2026

A pygmy shrew (\textit{Suncus etruscus}, ${\approx}2$\,g) sustains a resting heart rate near $1{,}000$\,beats\,min$^{-1}$ and dies within two years; an African elephant (${\approx}4{,}000$\,kg) beats โ€ฆ

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Physics Preprint PDF DOI

Some Properties and Uses of the Species Scale

Luis E. Ibanez ยท 2026

The 'Species Scale' has proved to be an important concept when studying consistent effective actions in Quantum Gravity. This is a short summary of my contribution to the Corfu Summer Institute in Sepโ€ฆ

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Mathematics Preprint PDF DOI

G\r{a}rding Polynomials

Hao Fang, Biao Ma ยท 2026

We introduce G\r{a}rding polynomials, a class of real multivariate polynomials defined via positivity regions invariant under translation by positive directions and closed under strictly positive affiโ€ฆ

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Computer Science Preprint PDF DOI

Online Coloring for Graphs of Large Odd Girth

Hirotaka Yoneda, Masataka Yoneda ยท 2026

We study the problem of online coloring for graphs with large odd girth. The best previously known algorithm uses $O(n^{1/2})$ colors, which was discovered by Kierstead in 1998. This algorithm works wโ€ฆ

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Mathematics Preprint PDF DOI

How large part of a graph can be covered by the neighborhoods of k vertices?

Janos Pach ยท 2026

Let $k\ge 2$ be fixed integer, $0<c<1$ a constant. Consider a graph $G$ with $n$ vertices and average degree $cn$. We answer a question of Simon Griffiths by showing that $G$ has $k$ vertices such thaโ€ฆ

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Mathematics Preprint PDF DOI

Structural properties of Bia{\l}ynicki-Birula decompositions

Teddy Gonzales, Chayim Lowen ยท 2026

We investigate several aspects of the Bialynicki-Birula decomposition of a smooth complete $\mathbb{G}_m$-variety with finite fixed locus. Our results include novel characterizations of when the Bialyโ€ฆ

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Mathematics Preprint PDF DOI

Structural description of (bull, house)-free graphs

Manoj Belavadi, Chinh T. Hoang ยท 2026

The bull is a graph consisting of a triangle and two pendant edges. The P_5 is the chordless path on five vertices. The house is the complement of a P_5. A graph is k-critical if it is k-chromatic butโ€ฆ

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Mathematics Preprint PDF DOI

Freidlin-G\"artner formula and asymptotic profile in reaction-diffusion equations

Luca Rossi ยท 2026

We address the question of the large-time behavior of solutions to reaction-diffusion equations in periodic media. We start with the description of the asymptotic shape of the invasion set, which is cโ€ฆ

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