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In 2006 J.G. Thompson conjectured: "If F is a field and A is in GL(n,F), then there is a permutation matrix P such that AP is cyclic, that is, the minimal polynomial of AP is also its characteristic polynomial" (open problem 16.95 in the…

Group Theory · Mathematics 2017-11-16 John D. Dixon

We show that the Friedlander-Mazur conjecture holds for the product of an elliptic curve with some smooth projective variety of dimension 3. Moreover, we show that the Friedlander-Mazur conjecture is stable under a surjective map. As…

Algebraic Geometry · Mathematics 2021-11-05 Jin Cao , Wenchuan Hu

Let $X$ be the product of a surface satisfying $b_2=\rho$ and of a curve over a finite field. We study a strong form of the integral Tate conjecture for $1$-cycles on $X$. We generalize and give unconditional proofs of several results of…

Algebraic Geometry · Mathematics 2025-07-23 Federico Scavia

We show that the Friedlander-Mazur conjecture holds for a complex smooth projective variety X of dimension three implies the standard conjectures hold for X. This together with a result of Friedlander yields the equivalence of the two…

Algebraic Geometry · Mathematics 2021-11-05 Jin Cao , Wenchuan Hu

In this research, an optimal algorithm for the Collatz conjecture is presented. Properties such as the convergence of the algorithm and an equation that relates the algorithm to the classical Collatz conjecture are obtained. It is validated…

General Mathematics · Mathematics 2024-07-23 Juan Carlos Riano-Rojas

We give an easy proof to show that every complex normal Toeplitz matrix is classified as either of type I or of type II. Instead of difference equations on elements in the matrix used in past studies, polynomial equations with coefficients…

Rings and Algebras · Mathematics 2007-05-23 Akio Arimoto

The polynomial relationship between elementary symmetric functions (Cauchy enumeration formula) is formulated via a ``raising operator" and Fock space construction. A simple graphical proof of this relation is proposed. The new operator…

Mathematical Physics · Physics 2020-08-04 Jerzy Kocik

The Collatz Conjecture (also known as the 3x+1 Problem) proposes that the following algorithm will, after a certain number of iterations, always yield the number 1: given a natural number, multiply by three and add one if the number is odd,…

Number Theory · Mathematics 2020-01-28 Matt Hohertz , Bahman Kalantari

For truncated Toeplitz operators, which are compressions of multiplication operators to model subspaces of the Hardy space $H^2$, we obtain criteria for commutation relations. The results show an analogy to the case of Toeplitz matrices,…

Functional Analysis · Mathematics 2013-05-30 Isabelle Chalendar , Dan Timotin

We prove a Schwarz-Jack lemma for holomorphic functions on the unit disk with the property that their maximum modulus on each circle about the origin is attained at a point on the positive real axis. With the help of this result, we…

Complex Variables · Mathematics 2026-04-10 Javad Mashreghi , Annika Moucha , Ryan O'Loughlin , Thomas Ransford , Oliver Roth

On the set of positive integers, we consider the iterative process that maps $n$ to either $\frac{3n+1}{2}$ or $\frac{n}{2}$ depending on the parity of $n$. The Collatz conjecture states that all such sequences eventually enter the trivial…

General Mathematics · Mathematics 2026-05-19 Olivier Rozier , Claude Terracol

I want to show one possibility to proof the Collatz conjecture, also called 3n+1 conjecture, for any natural number N. For this, I limit my analysis on the direct odd follower of every natural odd number and show the connections between the…

General Mathematics · Mathematics 2013-03-14 Carolin Zöbelein

In this paper we explore a family of congruences over $\N^\ast$ from which one builds a sequence of symmetric matrices related to the Mertens function. From the results of numerical experiments, we formulate a conjecture about the growth of…

Number Theory · Mathematics 2009-03-09 Jean-Paul Cardinal

We are concerned with the problem of real analytic regularity of the solutions of sums of squares with real analytic coefficients. Treves conjecture states that an operator of this type is analytic hypoelliptic if and only if all the strata…

Analysis of PDEs · Mathematics 2016-05-13 Paolo Albano , Antonio Bove , Marco Mughetti

Based on Stokes' theorem we derive a non-holomorphic functional calculus for matrices, assuming sufficient smoothness near eigenvalues, corresponding to the size of related Jordan blocks. It is then applied to the complex conjugation…

Functional Analysis · Mathematics 2017-01-31 Olavi Nevanlinna

We use a theorem by Gonzalez, Leon-Saavedra and Montes-Rodriguez to construct a class of coanalytic Toeplitz operators which have an infinite-dimensional closed subspace, where any non-zero vector is hypercyclic.

Functional Analysis · Mathematics 2014-01-09 Andrei Lishanskii

We continue the analysis in [3] of matrix convex functions of a fixed order defined in a real interval by differential methods as opposed to the characterization in terms of divided differences given by Kraus [5]. We amend and improve some…

Operator Algebras · Mathematics 2007-05-23 Frank Hansen , Jun Tomiyama

In this paper we resolve the arithmetic analogues of standard conjectures for an arithmetic variety, which are proposed by Gillet and Soule, into original standard conjectures and similar conjectures for two cycle class groups. One is the…

alg-geom · Mathematics 2008-02-03 Yuichiro Takeda

The periodic tiling conjecture asserts that any finite subset of a lattice $\mathbb{Z^d}$ which tiles that lattice by translations, in fact tiles periodically. We announce here a disproof of this conjecture for sufficiently large $d$, which…

Combinatorics · Mathematics 2022-09-20 Rachel Greenfeld , Terence Tao

We establish an analogue of the fundamental theorem of algebra for polynomial matrix equations, in which the matrices-coefficients and unknown matrix are assumed to be circulant matrices.

Commutative Algebra · Mathematics 2024-12-06 Vyacheslav M. Abramov
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