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Computing well-rounded twists of ideals in number fields has been done when the field degree is $2$. In this paper, we develop a new algorithm to detect whether a basis of an ideal $\mathfrak{I}$ in a cyclic cubic field $F$ yields a…

Number Theory · Mathematics 2025-08-26 Nam H. Le , Dat T. Tran , David Karpuk , Ha T. N. Tran

Let $k$ be a number field, $\mathbf{G}$ an algebraic group defined over $k$, and $\mathbf{G}(k)$ the group of $k$-rational points in $\mathbf{G}.$ We determine the set of functions on $\mathbf{G}(k)$ which are of positive type and…

Group Theory · Mathematics 2020-02-19 Bachir Bekka , Camille Francini

Let K be a compact Lie group and W a finite-dimensional real K-module. Let X be a K-stable real algebraic subset of W. Let I(X) denote the ideal of X in R[W] and let I_K(X) be the ideal generated by I(X)^K. We find necessary conditions and…

Representation Theory · Mathematics 2011-09-19 Gerald W. Schwarz

Let G be a simple algebraic group over an algebraically closed field k. We classify the spherical conjugacy classes of G.

Group Theory · Mathematics 2016-10-05 Mauro Costantini

Let $d$ be a square free integer and $L_d:=\mathbb{Q}(\zeta_{8},\sqrt{d})$. In the present work we determine all the fields $L_d$ such that the $2$-class group, $\mathrm{Cl}_2(L_d)$, of $L_d$ is of type $(2,4)$ or $(2,2,2)$.

Number Theory · Mathematics 2021-05-20 Abdelmalek Azizi , Mohamed Mahmoud Chems-Eddin , Abdelkader Zekhnini

Let $K$ be a global function field together with a place $\infty$, and $A$ the subring of functions regular outside $\infty$. In this paper we present an effective method to evaluate the (locally free) class number of an arbitrary…

Number Theory · Mathematics 2012-08-29 Fu-Tsun Wei , Chia-Fu Yu

By means of parametrized presentations of finite metabelian 3-groups, it is proved that the coclass cc(M) of the second 3-class group M=Gal(F_3^2(K)/K) of any algebraic number field K with elementary bicyclic 3-class group Cl_3(K)=(3,3) is…

Number Theory · Mathematics 2025-11-06 Siham Aouissi , Daniel C. Mayer

In 1976, Onabe discovered that, in contrast to the Neukirch-Uchida results that were proved around the same time, a number field $K$ is not completely characterized by its absolute abelian Galois group $A_K$. The first examples of…

Number Theory · Mathematics 2013-12-31 Athanasios Angelakis , Peter Stevenhagen

We derive a family of prime ideals of the Burnside Tambara functor for a finite group $G$. In the case of cyclic groups, this family comprises the entire prime spectrum. We include some partial results towards the same result for a larger…

Group Theory · Mathematics 2024-02-26 Maxine Calle , Sam Ginnett

For a symmetric algebra A over a field K of characteristic p > 0 K{\"u}lshammer constructed a descending sequence of ideals of the centre of A. If K is perfect this sequence was shown to be an invariant under derived equivalence and for…

Representation Theory · Mathematics 2017-06-01 Alexander Zimmermann

In this paper, we use $\mathcal D$-split sequences and derived equivalences to provide formulas for calculation of higher algebraic $K$-groups (or mod-$p$ $K$-groups) of certain matrix subrings which cover tiled orders, rings related to…

K-Theory and Homology · Mathematics 2015-03-19 Changchang Xi

Let n be an odd number and F an imaginary quadratic field with odd discriminant. We show that there exists infinitely many cubic fields K such that the class number of K is divisible by n and the Galois closure of K contains F.

Number Theory · Mathematics 2007-05-23 Ivan Chipchakov , Kalin Kostadinov

This paper contains an account of arbitrary cubic function fields of characteristic three. We define a standard form for an arbitrary cubic curve and consider its function field. By considering an integral basis for the maximal order of…

Number Theory · Mathematics 2010-09-06 Mark Bauer , Jonathan Webster

Algebraic cycles on complex projective space P(V) are known to have beautiful and surprising properties. Therefore, when V carries a real or quaternionic structure, it is natural to ask for the properties of the groups of real or…

Algebraic Topology · Mathematics 2012-08-27 H. Blaine Lawson, , Paulo Lima-Filho , Marie-Louise Michelsohn

For each real quadratic field we constructively show the existence of infinitely many exceptional quartic number fields containing that quadratic field. On the other hand, another infinite collection of quartic exceptional fields without…

Number Theory · Mathematics 2023-10-31 Aruna C , P Vanchinathan

We construct an infinite family of imaginary quadratic number fields with 2-class groups of type (2,2,2) whose Hilbert 2-class fields are finite.

Number Theory · Mathematics 2013-10-25 Franz Lemmermeyer

A subgroup of a group $G$ is called algebraic if it can be expressed as a finite union of solution sets to systems of equations. We prove that a non-elementary subgroup $H$ of an acylindrically hyperbolic group $G$ is algebraic if and only…

Group Theory · Mathematics 2017-02-07 Bryan Jacobson

For a prime $\ell$, let $h_\ell(K)$ denote the $\ell$-part of the class number of the number field $K$. We investigate upper bounds for $h_\ell(K)$ when $K$ is quadratic or cubic, particularly in the case in which the discriminant of $K$ is…

Number Theory · Mathematics 2025-01-07 D. R. Heath-Brown

In this paper, we compute the unit groups and the $2$-class numbers of the Fr\"ohlich's triquadratic fields $\KK=\mathbb{Q}(\sqrt{2},\sqrt{p},\sqrt{q})$, where $p$ and $q$ are two prime numbers such that ($p\equiv 1 \pmod8$ and $q\equiv 3…

Number Theory · Mathematics 2024-07-26 Mohamed Mahmoud Chems-Eddin

In this paper, we describe the higher even $K$-groups of the ring of integers of a number field in terms of class groups of an appropriate extension of the number field in question. This is a natural extension of the previous collective…

Number Theory · Mathematics 2023-11-22 Meng Fai Lim