Riemannian geometry | Riemannian manifolds | Metric geometry

Sub-Riemannian manifold

In mathematics, a sub-Riemannian manifold is a certain type of generalization of a Riemannian manifold. Roughly speaking, to measure distances in a sub-Riemannian manifold, you are allowed to go only along curves tangent to so-called horizontal subspaces. Sub-Riemannian manifolds (and so, a fortiori, Riemannian manifolds) carry a natural intrinsic metric called the metric of Carnot–Carathéodory. The Hausdorff dimension of such metric spaces is always an integer and larger than its topological dimension (unless it is actually a Riemannian manifold). Sub-Riemannian manifolds often occur in the study of constrained systems in classical mechanics, such as the motion of vehicles on a surface, the motion of robot arms, and the orbital dynamics of satellites. Geometric quantities such as the Berry phase may be understood in the language of sub-Riemannian geometry. The Heisenberg group, important to quantum mechanics, carries a natural sub-Riemannian structure. (Wikipedia).

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Emanuel Milman: Functional Inequalities on sub-Riemannian manifolds via QCD

We are interested in obtaining Poincar ́e and log-Sobolev inequalities on domains in sub-Riemannian manifolds (equipped with their natural sub-Riemannian metric and volume measure). It is well-known that strictly sub-Riemannian manifolds do not satisfy any type of Curvature-Dimension condi

From playlist Workshop: High dimensional measures: geometric and probabilistic aspects

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Ludovic Rifford: Geometric control and sub-Riemannian geodesics - Part I

Find this video and other talks given by worldwide mathematicians on CIRM's Audiovisual Mathematics Library: http://library.cirm-math.fr. And discover all its functionalities: - Chapter markers and keywords to watch the parts of your choice in the video - Videos enriched with abstracts, b

From playlist Geometry

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MATH331: Riemann Surfaces - part 1

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From playlist The Riemann Sphere

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Spectrum and abnormals in sub-Riemannian geometry: the 4D quasi-contact case - Nikhil Savale

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From playlist Mathematics

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Pierre Pansu: Differential forms and the Hölder equivalence problem - Part 1

Find this video and other talks given by worldwide mathematicians on CIRM's Audiovisual Mathematics Library: http://library.cirm-math.fr. And discover all its functionalities: - Chapter markers and keywords to watch the parts of your choice in the video - Videos enriched with abstracts, b

From playlist Geometry

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Riemannian Geometry - Definition: Oxford Mathematics 4th Year Student Lecture

Riemannian Geometry is the study of curved spaces. It is a powerful tool for taking local information to deduce global results, with applications across diverse areas including topology, group theory, analysis, general relativity and string theory. In these two introductory lectures

From playlist Oxford Mathematics Student Lectures - Riemannian Geometry

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Riemannian Geometry - Examples, pullback: Oxford Mathematics 4th Year Student Lecture

Riemannian Geometry is the study of curved spaces. It is a powerful tool for taking local information to deduce global results, with applications across diverse areas including topology, group theory, analysis, general relativity and string theory. In these two introductory lectures

From playlist Oxford Mathematics Student Lectures - Riemannian Geometry

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Z. Badreddine - Optimal transportation problem and MCP property on sub-Riemannian structures

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From playlist Journées Sous-Riemanniennes 2018

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Riemannian Exponential Map on the Group of Volume-Preserving Diffeomorphisms - Gerard Misiolek

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From playlist Mathematics

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Sachchidanand Prasad: Morse-Bott Flows and Cut Locus of Submanifolds

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From playlist 39th Annual Geometric Topology Workshop (Online), June 6-8, 2022

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Riemann Roch: genus 2 curves

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From playlist Algebraic geometry: extra topics

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Curvature of a Riemannian Manifold | Riemannian Geometry

In this lecture, we define the exponential mapping, the Riemannian curvature tensor, Ricci curvature tensor, and scalar curvature. The focus is on an intuitive explanation of the curvature tensors. The curvature tensor of a Riemannian metric is a very large stumbling block for many student

From playlist All Videos

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Boundary regularity for area minimizing currents and a question of Almgren - Camillo De Lellis

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From playlist Workshop on Mean Curvature and Regularity

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C. Sormani - Intrinsic Flat and Gromov-Hausdorff Convergence 1 (version temporaire)

We introduce various notions of convergence of Riemannian manifolds and metric spaces. We then survey results and open questions concerning the limits of sequences of Riemannian manifolds with uniform lower bounds on their scalar curvature. We close the course by presenting methods and the

From playlist Ecole d'été 2021 - Curvature Constraints and Spaces of Metrics

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Entropy of manifolds and of their fundamental group - Gerard Besson

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From playlist Mathematics

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Hodge theory and cycle theory of locally symmetric spaces – Nicolas Bergeron – ICM2018

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From playlist Geometry

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Riemann Roch: structure of genus 1 curves

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From playlist Algebraic geometry: extra topics

Related pages

Heisenberg group | Hamilton–Jacobi equation | Intrinsic metric | Tangent bundle | Manifold | Metric space | Lie group | Quadratic form | Hausdorff dimension | Carnot group | Mathematics | Integer | Hamiltonian mechanics | Subbundle | Riemannian manifold | Chow–Rashevskii theorem | Distribution (differential geometry) | Linear combination