Results 111 to 120 of about 71,381 (220)

On the induced geometry on surfaces in 3D contact sub-Riemannian\n manifolds [PDF]

, 2020
Davide Barilari, Ugo Boscain, Daniele Cannarsa   +2 more
openalex   +1 more source

Global and microlocal aspects of Dirac operators: Propagators and Hadamard states

Mathematische Nachrichten, Volume 298, Issue 9, Page 2942-2974, September 2025.
Abstract We propose a geometric approach to construct the Cauchy evolution operator for the Lorentzian Dirac operator on Cauchy‐compact globally hyperbolic 4‐manifolds. We realize the Cauchy evolution operator as the sum of two invariantly defined oscillatory integrals—the positive and negative Dirac propagators—global in space and in time, with ...
Matteo Capoferri, Simone Murro
wiley   +1 more source

Convex Hull Property and Exclosure Theorems for H-Minimal Hypersurfaces in Carnot Groups

Analysis and Geometry in Metric Spaces, 2016
In this paper, we generalize to sub-Riemannian Carnot groups some classical results in the theory of minimal submanifolds. Our main results are for step 2 Carnot groups.
Montefalcone Francescopaolo
doaj   +1 more source

Geometry of sub - Riemannian manifolds equipped with a semimetric quarter - symmetric connection

Ufa Mathematical Journal
On a sub-Riemannian manifold we introduce a semimetric quarter-symmetric connection by defining intrinsic metric connection and two structural endomorphisms preserving the distribution on a sub-Riemannian manifold.
A. Bukusheva, S. Galaev
semanticscholar   +1 more source

Existence of isoperimetric regions in sub-Finsler nilpotent groups

Analysis and Geometry in Metric Spaces
We consider a nilpotent Lie group with a bracket-generating distribution ℋ{\mathcal{ {\mathcal H} }} and an asymmetric left-invariant norm ∣⋅∣K{| \cdot | }_{K} induced by a convex body K⊆RkK\subseteq {{\mathbb{R}}}^{k} containing 0 in its interior.
Pozuelo Julián
doaj   +1 more source

Curvature exponent and geodesic dimension on Sard-regular Carnot groups

Analysis and Geometry in Metric Spaces
In this study, we characterize the geodesic dimension NGEO{N}_{{\rm{GEO}}} and give a new lower bound to the curvature exponent NCE{N}_{{\rm{CE}}} on Sard-regular Carnot groups.
Golo Sebastiano Nicolussi, Zhang Ye
doaj   +1 more source

Sub-Riemannian geometry on some step-two Carnot groups [PDF]

, 2021
Hongquan Li, Ye Zhang
openalex   +1 more source

Metric lines in the jet space

Analysis and Geometry in Metric Spaces
In the realm of sub-Riemannian manifolds, a relevant question is: what are the metric lines (isometric embedding of the real line)? The space of kk-jets of a real function of one real variable xx, denoted by Jk(R,R){J}^{k}\left({\mathbb{R}},{\mathbb{R}}),
Bravo-Doddoli Alejandro
doaj   +1 more source

Good continuation in 3D: the neurogeometry of stereo vision

Frontiers in Computer Science
Classical good continuation for image curves is based on 2D position and orientation. It is supported by the columnar organization of cortex, by psychophysical experiments, and by rich models of (differential) geometry.
Maria Virginia Bolelli, Maria Virginia Bolelli, Giovanna Citti, Alessandro Sarti, Steven W. Zucker   +4 more
doaj   +1 more source

Analytic torsion of nilmanifolds with (2, 3, 5) distributions

Analysis and Geometry in Metric Spaces
We consider generic rank two distributions on five-dimensional nilmanifolds and show that the analytic torsion of their Rumin complex coincides with the Ray-Singer torsion.
Haller Stefan
doaj   +1 more source