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The real time evolution of a scalar field in 0+1 dimensions is investigated on a complex time contour. The path integral formulation of the system has a sign problem, which is circumvented using the Complex Langevin equation. Measurement of…

High Energy Physics - Lattice · Physics 2023-09-13 Nina Maria Lampl , Dénes Sexty

We show that the spectral norm of a random $n_1\times n_2\times \cdots \times n_K$ tensor (or higher-order array) scales as $O\left(\sqrt{(\sum_{k=1}^{K}n_k)\log(K)}\right)$ under some sub-Gaussian assumption on the entries. The proof is…

Statistics Theory · Mathematics 2014-07-09 Ryota Tomioka , Taiji Suzuki

Let K be a multiquadratic number field. We investigate the average dimension of 2-Selmer groups over K for the family of all elliptic curves over the rational numbers (ordered by height). We give upper and lower bounds for this average. In…

Number Theory · Mathematics 2024-01-18 Ross Paterson

Canonical matrices are given for (a) bilinear forms over an algebraically closed or real closed field; (b) sesquilinear forms over an algebraically closed field and over real quaternions with any nonidentity involution; and (c) sesquilinear…

Representation Theory · Mathematics 2007-12-17 Roger A. Horn , Vladimir V. Sergeichuk

Several new verifiable conditions are established for block matrices with scalar diagonal blocks to have the numerical range equal the convex hull of at most k ellipses where k by k is the size of the smaller diagonal block. For k = 2,…

Functional Analysis · Mathematics 2020-02-25 Titas Geryba , Ilya M. Spitkovsky

We prove in some cases a formula for the Greenberg-Benois $\mathcal{L}$-invariant of the spin, standard and adjoint Galois representations associated with Siegel-Hilbert modular forms. In order to simplify the calculation, we give a new…

Number Theory · Mathematics 2018-05-10 Giovanni Rosso

The aim of this paper is to start the study of images of graded polynomials on full matrix algebras. We work with the matrix algebra $M_n(K)$ over a field $K$ endowed with its canonical $\mathbb{Z}_n$-grading (Vasilovsky's grading). We…

Rings and Algebras · Mathematics 2023-01-10 Lucio Centrone , Thiago Castilho de Mello

Let $K$ be an imaginary quadratic field. For an order $\mathcal{O}$ in $K$ and a positive integer $N$, let $K_{\mathcal{O},\,N}$ be the ray class field of $\mathcal{O}$ modulo $N\mathcal{O}$. We deal with various subjects related to…

Number Theory · Mathematics 2023-08-28 Ho Yun Jung , Ja Kyung Koo , Dong Hwa Shin , Dong Sung Yoon

Theory of numerical range and numerical radius for tensors is not studied much in the literature. In 2016, Ke {\it et al.} [Linear Algebra Appl., 508 (2016) 100-132] introduced first the notion of numerical range of a tensor via the…

Rings and Algebras · Mathematics 2025-08-08 Nirmal Chandra Rout , Krushnachandra Panigrahy , Debasisha Mishra

Let $k$ be a number field. We provide an asymptotic formula for the number of Galois extensions of $k$ with absolute discriminant bounded by some $X \geq 1$, as $X\to\infty$. We also provide an asymptotic formula for the closely related…

Number Theory · Mathematics 2024-06-07 Robert J. Lemke Oliver

We study the homogeneous involutions on the full square matrices over an algebraically closed field endowed with a division grading with commutative support. We obtain the classification of the isomorphism and equivalence classes for the…

Rings and Algebras · Mathematics 2026-01-30 Micael Said Garcia , Cassia Ferreira Sampaio

When p divides the ordering of Galois group, the distribution of the Sylow p-subgroup of Cl(K) is closely related to the problem of counting fields with certain specifications. Moreover, different orderings of number fields affect the…

Number Theory · Mathematics 2023-10-25 Weitong Wang

It has been shown that if $T$ is a complex matrix, then {\small\begin{align*} \omega(T)&=\frac{1}{n}\sup\left\{|\mathrm{Tr}\ X|;\ X\in W^n(T)\right\}\\ &=\frac{1}{n}\sup\left\{\|X\|_1;\ X\in W^n(T)\right\}\\ &= \sup\left\{ \omega(X);\ X\in…

Functional Analysis · Mathematics 2019-11-26 Mohsen Kian , Mahdi Dehghani , Mostafa Sattari

A new concept of a deformed numerical range $W^\rho(T)$ is introduced. Here $T$ is a bounded linear operator or a matrix and $ \rho \in[1,+\infty)$ is a parameter. Each $W^\rho(T)$ is a closed convex set that contains the spectrum of $T$.…

Functional Analysis · Mathematics 2025-05-02 Patryk Pagacz , Paweł Pietrzycki , Michał Wojtylak

Over an algebraically closed base field $k$ of characteristic 2, the ring $R^G$ of invariants is studied, $G$ being the orthogonal group O(n) or the special orthogonal group SO(n) and acting naturally on the coordinate ring $R$ of the…

Rings and Algebras · Mathematics 2014-07-31 M. Domokos , P. E. Frenkel

This paper is devoted to the study of the log-convexity of combinatorial sequences. We show that the log-convexity is preserved under componentwise sum, under binomial convolution, and by the linear transformations given by the matrices of…

Combinatorics · Mathematics 2010-08-17 Li Liu , Yi Wang

We investigate an enriched-categorical approach to a field of discrete mathematics. The main result is a duality theorem between a class of enriched categories (called $\overline{\mathbb{Z}}$- or $\overline{\mathbb{R}}$-categories) and that…

Category Theory · Mathematics 2019-04-19 Soichiro Fujii

In this paper, we consider infinite Galois extensions of number fields and study the relation between their local degrees and the structure of their Galois groups. It is known that, if $K$ is a number field and $L/K$ is an infinite Galois…

Number Theory · Mathematics 2017-08-31 Sara Checcoli

For a finite group $G$, we introduce a generalization of norm relations in the group algebra $\mathbb Q[G]$. We give necessary and sufficient criteria for the existence of such relations and apply them to obtain relations between the…

Number Theory · Mathematics 2025-04-07 Jean-François Biasse , Claus Fieker , Tommy Hofmann , Aurel Page

Motivated by long-standing conjectures on the discretization of classical inequalities in the Geometry of Numbers, we investigate a new set of parameters, which we call \emph{packing minima}, associated to a convex body $K$ and a lattice…

Metric Geometry · Mathematics 2021-01-20 Martin Henk , Matthias Schymura , Fei Xue