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Related papers: A note on Carnot geodesics in nilpotent Lie groups

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Many phenomena are naturally characterized by measuring continuous transformations such as shape changes in medicine or articulated systems in robotics. Modeling the variability in such datasets requires performing statistics on Lie groups,…

Methodology · Statistics 2025-08-19 Johannes Schade , Christoph von Tycowicz , Martin Hanik

In this article we show that the only 2-step nilpotent Lie groups which carry a non-degenerate left invariant Killing-Yano 2-form are the complex Lie groups. In the case of 2-step nilpotent complex Lie groups arising from connected graphs,…

Differential Geometry · Mathematics 2019-07-09 Adrián Andrada , Isabel G. Dotti

The present paper links the representation theory of Lie groupoids and infinite-dimensional Lie groups. We show that smooth representations of Lie groupoids give rise to smooth representations of associated Lie groups. The groups envisaged…

Group Theory · Mathematics 2019-05-21 Habib Amiri , Alexander Schmeding

Our goal is to find classes of convolution semigroups on Lie groups $G$ that give rise to interesting processes in symmetric spaces $G/K$. The $K$-bi-invariant convolution semigroups are a well-studied example. An appealing direction for…

Probability · Mathematics 2017-03-02 David Applebaum

We consider actions of non-compact simple Lie groups preserving an analytic rigid geometric structure of algebraic type on a compact manifold. The structure is not assumed to be unimodular, so an invariant measure may not exist. Ergodic…

Dynamical Systems · Mathematics 2009-01-06 Amos Nevo , Robert J. Zimmer

Lie theory is, beyond any doubt, an absolutely essential part of differential geometry. It is therefore necessary to seek its generalization to $\mathbb{Z}$-graded geometry. In particular, it is vital to construct non-trivial and explicit…

Differential Geometry · Mathematics 2025-11-10 Jan Vysoky

In this paper we characterize the geodesic dimension $N_{GEO}$ and give a new lower bound to the curvature exponent $N_{CE}$ on Sard-regular Carnot groups. As an application, we give an example of step-two Carnot group on which $N_{CE} >…

Metric Geometry · Mathematics 2024-07-30 Sebastiano Nicolussi Golo , Ye Zhang

We classify real 6-dimensional nilpotent Lie algebras for which the corresponding Lie group has a left-invariant complex structure, and estimate the dimensions of moduli spaces of such structures.

Differential Geometry · Mathematics 2007-05-23 Simon Salamon

A nonpolycyclic nilpotent-by-cyclic group Gamma can be expressed as the HNN extension of a finitely-generated nilpotent group N. The first main result is that quasi-isometric nilpotent-by-cyclic groups are HNN extensions of quasi-isometric…

Group Theory · Mathematics 2007-05-23 Ashley Reiter Ahlin

We construct families of $k$-step nilpotent symplectic Lie algebras associated with graphs, extending the construction given in [Pouseele-Tirao, JPAA 213 (2009)] for the 2-step case. We also show that, under mild conditions on the…

Rings and Algebras · Mathematics 2026-04-28 Josefina Barrionuevo , Paulo Tirao , Sonia Vera

This paper investigates some properties of complex structures on Lie algebras. In particular, we focus on $\textit{nilpotent}$ $\textit{complex structures}$ that are characterized by a suitable $J$-invariant ascending or descending central…

Differential Geometry · Mathematics 2022-02-07 Junze Zhang

We investigate the geodesic orbit property of pseudo-Riemannian nilmanifolds, specifically those known in the literature as pseudo $H$-type Lie groups -- i.e., 2-step nilpotent Lie groups of Heisenberg type equipped with a left invariant…

Differential Geometry · Mathematics 2026-03-06 Kenro Furutani , Irina Markina , Yurii Nikonorov

In general, the study of gradations has always represented a cornerstone in algebra theory. In particular, \textit{naturally graded} seems to be the first and the most relevant gradation when it comes to nilpotent algebras, a large class of…

Rings and Algebras · Mathematics 2024-01-25 Luisa Camacho , Rosa M. Navarro , J. M. Sánchez

In this paper, we introduce and study five families of Lie groups in degenerate Clifford geometric algebras. These Lie groups preserve the even and odd subspaces and some other subspaces under the adjoint representation and the twisted…

Rings and Algebras · Mathematics 2024-01-09 E. R. Filimoshina , D. S. Shirokov

Abnormal extremals on four-dimensional connected Lie groups with left-invariant sub-Finsler quasimetric, defined by a seminorm on a two-dimensional subspace of the Lie algebra generating the algebra, are found. In terms of structure…

Differential Geometry · Mathematics 2020-12-22 Valera Berestovskii , Irina Zubareva

The present paper deals with the stability analysis for the geodesic flow of a step-two nilpotent Lie group equipped with a left-invariant pseudo-Riemannian metric. The Lie-Poisson equation can be described in terms of the so-called…

Dynamical Systems · Mathematics 2026-02-23 Genki Ishikawa , Daisuke Tarama

The goals of this article are twofold : 1) to compute the conjugate locus of a geodesic that lies in the center of a simply connected, 2-step nilpotent Lie group with a left invariant metric 2) compare the isometry types of two such…

Differential Geometry · Mathematics 2015-07-22 Patrick Eberlein

We analyze subsets of Carnot groups that have intrinsic constant normal, as they appear in the blowup study of sets that have finite sub-Riemannian perimeter. The purpose of this paper is threefold. First, we prove some mild regularity and…

Differential Geometry · Mathematics 2019-10-29 Costante Bellettini , Enrico Le Donne

In this paper we show that topological subgroupoids of Lie groupoids, under special circumstances are Lie subgroupoids. Giving an example, we indicate that having the same topological dimension is a necessary condition for topological…

Differential Geometry · Mathematics 2018-03-15 A. R. Armakan , M. R. Farhangdoost , F. Gorlizkhatami , T. Nasirzadeh

The second de Rham cohomology groups of nilpotent orbits in non-compact real forms of classical complex simple Lie algebras are explicitly computed. Furthermore, the first de Rham cohomology groups of nilpotent orbits in non-compact…

Group Theory · Mathematics 2022-03-29 Indranil Biswas , Pralay Chatterjee , Chandan Maity