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Related papers: Rational approximations of irrational numbers

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We develop the theory of Diophantine approximation for systems of simultaneously small linear forms, which coefficients are drawn from any given analytic non-degenerate manifolds. This setup originates from a problem of Sprind\v{z}uk from…

Number Theory · Mathematics 2017-07-04 Victor Beresnevich , Vasili Bernik , Natalia Budarina

Let $1<k<14/5$, $\lambda_1,\lambda_2,\lambda_3$ and $\lambda_4$ be non-zero real numbers, not all of the same sign such that $\lambda_1/\lambda_2$ is irrational and let $\omega$ be a real number. We prove that the inequality…

Number Theory · Mathematics 2024-06-26 Alessandro Gambini

In the present paper we give very simple general statements which deal with approximation of a real number by rationals and are related to isolation phenomenon. In particular we study functions $ f(x)>f_1(x)>0$ such that existence of…

Number Theory · Mathematics 2025-10-16 Sergei Pitcyn , Nikolay Moshchevitin

In this survey article, we explore a central theme in Diophantine approximation inspired by a celebrated result of Besicovitch on the Hausdorff dimension of well approximable real numbers. We outline some of the key developments stemming…

Number Theory · Mathematics 2025-09-18 Victor Beresnevich , Sanju Velani

This paper is motivated by two problems in the theory of Diophantine approximation, namely, Davenport's problem regarding badly approximable points on submanifolds of a Euclidean space and Schmidt's problem regarding the intersections of…

Number Theory · Mathematics 2016-04-01 Victor Beresnevich

In this paper, we consider the intrinsic Diophantine approximation on the triadic Cantor set $\mathcal{K}$, i.e. approximating the points in $\mathcal{K}$ by rational numbers inside $\mathcal{K}$, a question posed by K. Mahler. By using…

Number Theory · Mathematics 2021-03-02 Bo Tan , Baowei Wang , Jun Wu

Let $[\, x\,]$ denote the integer part of a real number $x$. Assume that $\lambda_1,\lambda_2,\lambda_3$ are nonzero real numbers, not all of the same sign, that $\lambda_1/\lambda_2$ is irrational, and that $\eta$ is real. Let…

Number Theory · Mathematics 2026-03-25 S. I. Dimitrov

The irrationality exponent of a real number measures how well that number can be approximated by rationals. Real numbers with irrationality exponent strictly greater than $2$ are transcendental numbers, and form a set with rich fractal…

Number Theory · Mathematics 2025-12-30 Hiroki Takahasi

A rational Diophantine m-tuple is a set of m nonzero rationals such that the product of any two of them increased by 1 is a perfect square. The first rational Diophantine quadruple was found by Diophantus, while Euler proved that there are…

Number Theory · Mathematics 2017-03-08 Andrej Dujella , Matija Kazalicki , Miljen Mikić , Márton Szikszai

The inhomogeneous Khintchine-Groshev Theorem is a classical generalization of Khintchine's Theorem in Diophantine approximation, by approximating points in $\mathbb{R}^m$ by systems of linear forms in $n$ variables. Analogous to the…

Number Theory · Mathematics 2023-12-05 Manuel Hauke

We first propose two conjectural estimates on Diophantine approximation of logarithms of algebraic numbers. Next we discuss the state of the art and we give further partial results on this topic.

Number Theory · Mathematics 2007-05-23 Michel Waldschmidt

In 2004, J.C. Tong found bounds for the approximation quality of a regular continued fraction convergent of a rational number, expressed in bounds for both the previous and next approximation. We sharpen his results with a geometric method…

Number Theory · Mathematics 2009-08-25 Cor Kraaikamp , Ionica Smeets

The Duffin-Schaeffer conjecture is a central open problem in metric number theory. Let $\psi~\mathbb{N} \mapsto \mathbb{R}$ be a non-negative function, and set $\mathcal{E}_n :=\bigcup \left( \frac{a - \psi(n)}{n},\frac{a+\psi(n)}{n}…

Number Theory · Mathematics 2019-07-11 Christoph Aistleitner

Let $E\subset [0,1]$ be a set that supports a probability measure $\mu$ with the property that $|\widehat{\mu}(t)|\ll (\log |t|)^{-A}$ for some constant $A>2.$ Let $\mathcal{A}=(q_n)_{n\in \N}$ be a positive, real-valued, lacunary sequence.…

Number Theory · Mathematics 2024-09-06 Bo Tan , Qing-Long Zhou

This paper is concerned with the study of diagonal Diophantine inequalities of fractional degree $ \theta ,$ where $ \theta >2$ is real and non-integral. For fixed non-zero real numbers $ \lambda_i $ not all of the same sign we write…

Number Theory · Mathematics 2021-08-02 Constantinos Poulias

We give an easy optimal bound for the dimension of the subspaces generated by the best Diophantine approximations.

Number Theory · Mathematics 2023-04-19 Nikolay Moshchevitin

Given any irrational number $\alpha$, we show that for any $0<\theta<6/17$, there are infinitely many $y$-smooth (friable) numbers $n$ such that $$\|n\alpha\| < n^{-\theta},$$ where $(\log n)^C\leq y\leq n$ for some large constant $C>0$.…

Number Theory · Mathematics 2026-03-31 Kunjakanan Nath , Habibur Rahaman

There are numerous ways to represent real numbers. We may use, e.g., Cauchy sequences, Dedekind cuts, numerical base-10 expansions, numerical base-2 expansions and continued fractions. If we work with full Turing computability, all these…

Logic · Mathematics 2020-03-30 Ivan Georgiev , Lars Kristiansen , Frank Stephan

We study diophantine equations of the form ${a_1 + \ldots + a_n = 0}$ where the $a_i$'s are assumed to be coprime and to satisfy certain subsum conditions. We are interested in the limit superior of the qualities of the admissible solutions…

Number Theory · Mathematics 2025-07-17 Rupert Hölzl , Sören Kleine , Frank Stephan

To account for the first proof of existence of an irrational magnitude, historians of science as well as commentators of Aristotle refer to the texts on the incommensurability of the diagonal in Prior Analytics, since they are the most…

History and Overview · Mathematics 2014-08-12 Salomon Ofman