Results 111 to 120 of about 70,602 (222)
Local non-injectivity of the exponential map at critical points in sub-Riemannian geometry [PDF]
Nonlinear Analysis, 2022 S. Borza, W. Klingenberg
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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
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Stochastic Multisymplectic PDEs and Their Structure‐Preserving Numerical Methods
Studies in Applied Mathematics, Volume 155, Issue 3, September 2025.ABSTRACT We construct stochastic multisymplectic systems by considering a stochastic extension to the variational formulation of multisymplectic partial differential equations proposed in Hydon [Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, 461 (2005): 1627–1637].
Ruiao Hu, Linyu Peng
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Analysis and Geometry in Metric Spaces, 2018 Carnot groups are distinguished spaces that are rich of structure: they are those Lie groups equipped with a path distance that is invariant by left-translations of the group and admit automorphisms that are dilations with respect to the distance.
Le Donne Enrico
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Sub-Riemannian Geometry in Image Processing and Modeling of the Human Visual System
Nelineinaya Dinamika, 2019 This paper summarizes results of a sequence of works related to usage of sub-Riemannian (SR) geometry in image processing and modeling of the human visual system. In recent research in psychology of vision (J. Petitot, G.Citti, A.
Alexey Pavlovich Mashtakov
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Projection Methods for some Constrained Systems [PDF]
, 2011 This article is concerned with a geometric tool given by a pair of projector operators defined by almost product structures on finite dimensional manifolds, polarized by a distribution of constant rank and also endowed with some geometric structures ...
Paulo, Paulo Pitanga, R. Rodrigues
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Closed geodesics and the first Betti number
Proceedings of the London Mathematical Society, Volume 131, Issue 3, September 2025.Abstract We prove that, on any closed manifold of dimension at least two with non‐zero first Betti number, a C∞$C^\infty$ generic Riemannian metric has infinitely many closed geodesics, and indeed closed geodesics of arbitrarily large length. We derive this existence result combining a theorem of Mañé together with the following new theorem of ...
Gonzalo Contreras, Marco Mazzucchelli
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The sphere and the cut locus at a tangency point in two-dimensional almost-Riemannian geometry
, 2010 We study the tangential case in 2-dimensional almost-Riemannian geometry. We analyse the connection with the Martinet case in sub-Riemannian geometry. We compute estimations of the exponential map which allow us to describe the conjugate locus and the ...
Bonnard, Bernard +3 more
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Asymptotics of quantum 6j$6j$‐symbols and generalized hyperbolic tetrahedra
Journal of Topology, Volume 18, Issue 3, September 2025.Abstract We establish the geometry behind the quantum 6j$6j$‐symbols under only the admissibility conditions as in the definition of the Turaev–Viro invariants of 3‐manifolds. As a classification, we show that the 6‐tuples in the quantum 6j$6j$‐symbols give in a precise way to the dihedral angles of (1) a spherical tetrahedron, (2) a generalized ...
Giulio Belletti, Tian Yang
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A survey on Inverse mean curvature flow in ROSSes
Complex Manifolds, 2017 In this survey we discuss the evolution by inverse mean curvature flow of star-shaped mean convex hypersurfaces in non-compact rank one symmetric spaces.
Pipoli Giuseppe
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