English
Related papers

Related papers: Normalizers of tori

200 papers

We identify a link between regular matroids and torus representations all of whose isotropy groups have an odd number of components. Applying Seymour's 1980 classification of the former objects, we obtain a classification of the latter. In…

Differential Geometry · Mathematics 2025-06-12 Lee Kennard , Michael Wiemeler , Burkhard Wilking

We prove that the set of elements of a given finite order in the connected component $N_w$ of the normalizer $N_G(T)$ of a maximal torus $T$ of a semisimple group $G$ is either empty or a disjoint union of finitely many irreducible…

Group Theory · Mathematics 2026-04-10 Ivan Arzhantsev , Alexey Galt , Alexey Staroletov

The Tits core G^+ of a totally disconnected locally compact group G is defined as the abstract subgroup generated by the closures of the contraction groups of all its elements. We show that a dense subgroup is normalised by the Tits core if…

Group Theory · Mathematics 2014-05-15 Pierre-Emmanuel Caprace , Colin D. Reid , George A. Willis

We study the space of conjugacy classes of subgroups of a compact Lie group G whose identity component is a torus, and consider how various invariants of subgroups behave as sheaves over this space. This feeds in to the author's programme…

Algebraic Topology · Mathematics 2025-10-20 J. P. C. Greenlees

By a theorem of Banyaga the group of diffeomorphisms of a manifold $P$ preserving a regular contact form $\alpha$ is a central $S^1$ extension of the commutator of the group of symplectomorphisms of the base $B = P/S^1$. We show that if $T$…

Symplectic Geometry · Mathematics 2007-05-23 Eugene Lerman

Let us consider an $n$-dimensional complex torus $T^{2n}_{J=T}:=\mathbb{C}^n/2\pi(\mathbb{Z}^n \oplus T\mathbb{Z}^n)$. Here, $T$ is a complex matrix of order $n$ whose imaginary part is positive definite. In particular, when we consider the…

Differential Geometry · Mathematics 2021-01-06 Kazushi Kobayashi

A Lie group is a group that is also a differentiable manifold, such that the group operation is continuous respect to the topological structure. To every Lie group we can associate its tangent space in the identity point as a vector space,…

Representation Theory · Mathematics 2015-09-29 Changwei Zhou

A connected component of an affine algebraic group is called periodic if all its elements have finite order. We give a characterization of periodic components in terms of automorphisms with finite number of fixed points. It is also…

Algebraic Geometry · Mathematics 2015-05-13 S. N. Fedotov

Let X be a normal affine T-variety of complexity at most one over a perfect field k, where T stands for the split algebraic torus. Our main result is a classification of additive group actions on X that are normalized by the T-action. This…

Algebraic Geometry · Mathematics 2016-01-28 Kevin Langlois , Alvaro Liendo

In this paper we classify Legendrian and transverse knots in the knot types obtained from positive torus knots by cabling. This classification allows us to demonstrate several new phenomena. Specifically, we show there are knot types that…

Geometric Topology · Mathematics 2014-11-11 John B. Etnyre , Douglas J. LaFountain , Bulent Tosun

Given a simple connected compact Lie group $K$ and a maximal torus $T$ of $K$, the Weyl group $W=N_K(T)/T$ naturally acts on $T$. First, we use the combinatorics of the (extended) affine Weyl group to provide an explicit $W$-equivariant…

Algebraic Topology · Mathematics 2023-08-30 Arthur Garnier

We study the existence of infinite-dimensional invariant tori in a mechanical system of infinitely many rotators weakly interacting with each other. We consider explicitly interactions depending only on the angles, with the aim of…

Dynamical Systems · Mathematics 2024-04-16 Livia Corsi , Guido Gentile , Michela Procesi

We consider aspects of the geometry and topology of nilpotent orbits in finite-dimensional complex simple Lie algebras. In particular, we give the equivariant cohomologies of the regular and minimal nilpotent orbits with respect to the…

Algebraic Geometry · Mathematics 2015-12-29 Peter Crooks

In this paper, we study a mirror duality on a generalized complex torus and a noncommutative complex torus. First, we derive a symplectic version of Riemann condition using mirror duality on ordinary complex tori. Based on this we will find…

High Energy Physics - Theory · Physics 2008-12-18 Eunsang Kim , Hoil Kim

We give a constructive proof of the existence of lower dimensional elliptic tori in nearly integrable Hamiltonian systems. In particular we adapt the classical Kolmogorov's normalization algorithm to the case of planetary systems, for which…

Mathematical Physics · Physics 2014-01-28 Antonio Giorgilli , Ugo Locatelli , Marco Sansottera

An \emph{affine subtorus} of the compact torus $T=(S^1)^n$ is a translated copy of a Lie subgroup. Given a finite collection $T_1,\ldots, T_k$ of such subtori, and a prime $p$, we describe an explicit chain complex that calculates the group…

Algebraic Topology · Mathematics 2026-01-14 Alexey G. Gorinov , Alexander V. Zakharov

If a finite quasisimple group G with simple quotient S is embedded into a suitable classical group X through the smallest degree of a projective representation of S, then the normalizer of G in X is a maximal subgroup of X, up to two series…

Group Theory · Mathematics 2020-07-10 Gerhard Hiss

We classify the possible behaviour of Poincar\'e-Dulac normal forms for dynamical systems in $R^n$ with nonvanishing linear part and which are equivariant under (the fundamental representation of) all the simple compact Lie algebras and…

Mathematical Physics · Physics 2009-11-07 Giuseppe Gaeta

We consider the action of a subtorus of the big torus on a toric variety. The aim of the paper is to define a natural notion of a quotient for this setting and to give an explicit algorithm for the construction of this quotient from the…

Algebraic Geometry · Mathematics 2007-05-23 A. A'Campo-Neuen , J. Hausen

We give a normalizer decomposition for a p-local compact group (S, F, L) that describes |L| as a homotopy colimit indexed over a finite poset. Our work generalizes the normalizer decompositions for finite groups due to Dwyer, for p-local…

Algebraic Topology · Mathematics 2023-01-24 Eva Belmont , Natalia Castellana , Jelena Grbic , Kathryn Lesh , Michelle Strumila