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Related papers: Approximating reals by sums of rationals

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This paper offers a solution method that allows one to find exact values for a large class of convergent series of rational terms. Sums of this form arise often in problems dealing with Quantum Field Theory.

Mathematical Physics · Physics 2007-05-23 Costas Efthimiou

In 1969, H. Davenport and W. M. Schmidt studied the problem of approximation to a real number \xi by algebraic integers of degree at most three. They did so, using geometry of numbers, by resorting to the dual problem of finding…

Number Theory · Mathematics 2007-05-23 Damien Roy

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

Using a method of H. Davenport and W. M. Schmidt, we show that, for each positive integer n, the ratio 2/n is the optimal exponent of simultaneous approximation to real irrational numbers 1) by all conjugates of algebraic numbers of degree…

Number Theory · Mathematics 2015-05-13 Guillaume Alain

We give necessary and sufficient topological conditions for a simple closed curve on a real rational surface to be approximable by smooth rational curves. We also study approximation by smooth rational curves with given complex…

Algebraic Geometry · Mathematics 2025-05-26 János Kollár , Frédéric Mangolte

Let $A$ be a finite set of positive real numbers. We present a sum-division estimate: |A+A|^2|A/A|\geq\frac{|A|^4}{4}.

Number Theory · Mathematics 2009-05-16 Liangpan Li , Jian Shen

We explore an algorithm for approximating roots of integers, discuss its motivation and derivation, and analyze its convergence rates with varying parameters and inputs. We also perform comparisons with established methods for approximating…

Numerical Analysis · Mathematics 2021-01-11 William Gerst

A simple proof is given of the known fact that an m-times continuously differentiable function on the real line can be approximated along with its derivatives by an entire function and its respective derivatives.

Complex Variables · Mathematics 2019-08-15 Paul M. Gauthier , Julie Kienzle

Approximation theory is concerned with the ability to approximate functions by simpler and more easily calculated functions. The first question we ask in approximation theory concerns the {\it possibility of approximation}. Is the given…

Classical Analysis and ODEs · Mathematics 2007-05-23 Allan Pinkus

We prove new upper bounds on the number of representations of rational numbers $\frac{m}{n}$ as a sum of $4$ unit fractions, giving five different regions, depending on the size of $m$ in terms of $n$. In particular, we improve the most…

Number Theory · Mathematics 2020-12-14 Christian Elsholtz , Stefan Planitzer

We introduce and study expansions of real numbers with respect to two integer bases.

Dynamical Systems · Mathematics 2026-02-04 Jörg Neunhäuserer

The multiplicative theory of a set of numbers (which could be natural, integer, rational, real or complex numbers) is the first-order theory of the structure of that set with (solely) the multiplication operation (that set is taken to be…

Logic · Mathematics 2021-11-30 Saeed Salehi

We study the rational approximation properties of special manifolds defined by a set of polynomials with rational coefficients. Mostly we will assume the case of all polynomials to depend on only one variable. In this case the manifold can…

Number Theory · Mathematics 2018-12-31 Johannes Schleischitz

We provide an upper bound on the uniform exponent of approximation to a triple (xi, xi^2, xi^3) by rational numbers with the same denominator, valid for any transcendental real number xi. This upper bound refines a previous result of…

Number Theory · Mathematics 2015-05-13 Damien Roy

A basic question of Diophantine approximation, which is the first issue we discuss, is to investigate the rational approximations to a single real number. Next, we consider the algebraic or polynomial approximations to a single complex…

Number Theory · Mathematics 2009-08-28 Michel Waldschmidt

We relate a previous result of ours on families of Diophantine equations having only trivial solutions with a result on the approximation of an algebraic number by products of rational numbers and units. We compare this approximation with a…

Number Theory · Mathematics 2013-12-30 Claude Levesque , Michel Waldschmidt

We compute the constant of approximation for an arbitrary rational point on an arbitrary smooth cubic hypersurface $X$ over a number field $k$, provided that there is a $k$-rational line somewhere on $X$. In the process, we verify the Coba…

Algebraic Geometry · Mathematics 2023-10-04 David McKinnon

We consider the problem of Diophantine approximation on semisimple algebraic groups by rational points with restricted numerators and denominators and establish a quantitative approximation result for all real points in the group by…

Dynamical Systems · Mathematics 2014-11-04 Alexander Gorodnik , Shirali Kadyrov

Numerical approximate computation can solve large and complex problems fast. It has the advantage of high efficiency. However it only gives approximate results, whereas we need exact results in many fields. There is a gap between…

Algebraic Geometry · Mathematics 2015-06-26 Jingzhong Zhang , Yong Feng

In the present article, modeling certain rational numbers, that are represented in terms of Cantor series, are described. The statements on relations between digits in the representations of rational numbers by Cantor series (for the case…

Number Theory · Mathematics 2021-01-05 Symon Serbenyuk