English
Related papers

Related papers: Perfect forms over totally real number fields

200 papers

A positive definite quadratic form is called perfect, if it is uniquely determined by its arithmetical minimum and the integral vectors attaining it. In this self-contained survey we explain how to enumerate perfect forms in $d$ variables…

Number Theory · Mathematics 2011-10-20 Achill Schuermann

We give an upper bound for the norm of the determinant of additively indecomposable, totally positive definite quadratic forms defined over the ring of integers of totally real number fields. We apply these results to find lower and upper…

Number Theory · Mathematics 2025-10-10 Magdaléna Tinková , Pavlo Yatsyna

An integral quadratic form is called strictly $n$-regular if it primitively represents all quadratic forms in $n$ variables that are primitively represented by its genus. For any $n \geq 2$, it will be shown that there are only finitely…

Number Theory · Mathematics 2017-06-14 Wai Kiu Chan , Alicia Marino

In this work, we compute the perfect forms for all imaginary quadratic fields of absolute discriminant up to $5000$ and study the number and types of the polytopes that arise. We prove a bound on the combinatorial types of polytopes that…

Number Theory · Mathematics 2021-05-04 Kristen Scheckelhoff , Kalani Thalagoda , Dan Yasaki

In this article, the standard correspondence between the ideal class group of a quadratic number field and the equivalence classes of binary quadratic forms of given discriminant is generalized to any base number field of narrow class…

Number Theory · Mathematics 2023-07-18 Kristýna Zemková

In this paper, we revisit the theory of perfect unary forms over real quadratic fields. Specifically, we deduce an infinite family of real quadratic fields $\mathbb{Q}(\sqrt{d})$ when $d=2$ or $3$ mod $4$, such that there are three classes…

Number Theory · Mathematics 2024-04-03 Christian Porter

Every quadratic form represents 0; therefore, if we take any number of quadratic forms and ask which integers are simultaneously represented by all members of the collection, we are guaranteed a nonempty set. But when is that set more than…

Number Theory · Mathematics 2017-08-17 Christopher Donnay , Havi Ellers , Kate O'Connor , Katherine Thompson , Erin Wood

In this paper, we introduce the notion of unit reducibility for number fields, that is, number fields in which all positive unary forms attain their nonzero minimum at a unit. Furthermore, we investigate the link between unit reducibility…

Number Theory · Mathematics 2022-08-02 Alar Leibak , Christian Porter , Cong Ling

A positive definite integral quadratic form is said to be almost (primitively) universal if it (primitively) represents all but at most finitely many positive integers. In general, almost primitive universality is a stronger property than…

Number Theory · Mathematics 2020-05-25 A. G. Earnest , B. L. K. Gunawardana

George Voronoi (1908-09) introduced two important reduction methods for positive quadratic forms: the reduction with perfect forms, and the reduction with L-type domains. A form is perfect if can be reconstructed from all representations of…

Metric Geometry · Mathematics 2007-05-23 Robert Erdahl , Konstantin Rybnikov

In this paper, we study additively indecomposable quadratic forms over real biquadratic and simplest cubic fields. In particular, we show that over these fields, we can always find such a classical form in 2 variables, which differs from…

Number Theory · Mathematics 2026-02-10 Simona Fryšová , Magdaléna Tinková

A (positive definite and integral) quadratic form $f$ is said to be $\textit{universal}$ if it represents all positive integers, and is said to be $\textit{primitively universal}$ if it represents all positive integers primitively. We also…

Number Theory · Mathematics 2022-03-01 Jangwon Ju , Daejun Kim , Kyoungmin Kim , Mingyu Kim , Byeong-Kweon Oh

We present an adaptation of Voronoi theory for imaginary quadratic number fields of class number greater than 1. This includes a characterisation of extreme Hermitian forms which is analogous to the classic characterisation of extreme…

Number Theory · Mathematics 2013-04-03 Oliver Braun , Renaud Coulangeon

Let $\mathfrak o$ be the ring of integers of a totally real number field. If $f$ is a quadratic form over $\mathfrak o$ and $g$ is another quadratic form over $\mathfrak o$ which represents all proper subforms of $f$, does $g$ represent…

Number Theory · Mathematics 2023-09-25 Wai Kiu Chan , Byeong-Kweon Oh

We prove an explicit upper bound on the number of real quadratic fields that admit a universal quadratic form of a given rank, thus establishing a density zero statement. More generally, we obtain such a result for totally positive definite…

Number Theory · Mathematics 2025-05-23 Vitezslav Kala , Pavlo Yatsyna , Błażej Żmija

We investigate generalized quadratic forms with values in the set of rational integers over quadratic fields. We characterize the real quadratic fields which admit a positive definite binary generalized form of this type representing every…

We study real quadratic fields $\mathbb{Q}(\sqrt{D})$ such that, for a given rational integer $m$, all $m$-multiples of totally positive integers are sums of squares. We prove quite sharp necessary and sufficient conditions for this to…

Number Theory · Mathematics 2022-10-18 Martin Raška

We study universal quadratic forms over totally real number fields using Dedekind zeta functions. In particular, we prove an explicit upper bound for the rank of universal quadratic forms over a given number field $K$, under the assumption…

Number Theory · Mathematics 2025-10-27 Vítězslav Kala , Mentzelos Melistas

For a positive integer $m$, a (positive definite integral) quadratic form is called primitively $m$-universal if it primitively represents all quadratic forms of rank $m$. It was proved in arXiv:2202.13573 that there are exactly $107$…

Number Theory · Mathematics 2023-09-06 Byeong-Kweon Oh , Jongheun Yoon

We study the minimal number of variables required by a totally positive definite diagonal universal quadratic form over a real quadratic field $\mathbb Q(\sqrt D)$ and obtain lower and upper bounds for it in terms of certain sums of…

Number Theory · Mathematics 2018-07-05 Valentin Blomer , Vítězslav Kala
‹ Prev 1 2 3 10 Next ›