Fractals | Measures (measure theory) | Dimension theory | Metric geometry
In mathematics, Hausdorff measure is a generalization of the traditional notions of area and volume to non-integer dimensions, specifically fractals and their Hausdorff dimensions. It is a type of outer measure, named for Felix Hausdorff, that assigns a number in [0,∞] to each set in or, more generally, in any metric space. The zero-dimensional Hausdorff measure is the number of points in the set (if the set is finite) or ∞ if the set is infinite. Likewise, the one-dimensional Hausdorff measure of a simple curve in is equal to the length of the curve, and the two-dimensional Hausdorff measure of a Lebesgue-measurable subset of is proportional to the area of the set. Thus, the concept of the Hausdorff measure generalizes the Lebesgue measure and its notions of counting, length, and area. It also generalizes volume. In fact, there are d-dimensional Hausdorff measures for any d ≥ 0, which is not necessarily an integer. These measures are fundamental in geometric measure theory. They appear naturally in harmonic analysis or potential theory. (Wikipedia).
An introduction to the Gromov-Hausdorff distance
Title: An introduction to the Gromov-Hausdorff distance Abstract: We give a brief introduction to the Hausdorff and Gromov-Hausdorff distances between metric spaces. The Hausdorff distance is defined on two subsets of a common metric space. The Gromov-Hausdorff distance is defined on any
From playlist Tutorials
Hausdorff School: Introduction by Karl-Theodor Sturm
Presentation of the Hausdorff School by Karl-Theodor Sturm, coordinator of the Hausdorff Center. The “Hausdorff School for Advanced Studies in Mathematics” is an innovative new program for postdocs by the Hausdorff Center. The official inauguration took place on October 20, 2015.
From playlist Inauguration of Hausdorff School 2015
Hausdorff School: Lecture by Jean-Pierre Bourguignon
Inauguration of the Hausdorff School The “Hausdorff School for Advanced Studies in Mathematics” is an innovative new program for postdocs by the Hausdorff Center. The official inauguration took place on October 20, 2015. Lecture by Jean-Pierre Bourguignon on "Sound, Shape, and Harmony –
From playlist Inauguration of Hausdorff School 2015
Hausdorff Center for Mathematics
The Hausdorff Center for Mathematics (HCM) capitalizes on a broad vision of mathematics, ranging from pure mathematics, to contributions to quantative modeling in economics and the natural sciences, to industrial applications. HCM strives to serve the international mathematical community a
From playlist Hausdorff Center goes public
What is the distance between two sets of points? | Hausdorff Distance
What is the distance between two sets of points is a non-trivial question that has applications all over the place, from bioinformatics and computer science to fractal geometry. In this video, I'll give a bit of motivation, introduce the delta expansion of a set and then give the distance
From playlist The New CHALKboard
Hausdorff Example 3: Function Spaces
Point Set Topology: For a third example, we consider function spaces. We begin with the space of continuous functions on [0,1]. As a metric space, this example is Hausdorff, but not complete. We consider Cauchy sequences and a possible completion.
From playlist Point Set Topology
Hausdorff Example 1: Cofinite Topology
Point Set Topology: We recall the notion of a Hausdorff space and consider the cofinite topology as a source of non-Hausdorff examples. We also note that this topology is always compact.
From playlist Point Set Topology
Quantitative propagation for solutions of elliptic equations – A. Logunov & E. Malinnikova – ICM2018
Partial Differential Equations | Geometry Invited Lecture 10.11 | 5.12 Quantitative propagation of smallness for solutions of elliptic equations Alexander Logunov & Eugenia Malinnikova Abstract: Let u be a solution to an elliptic equation div(A∇u)=0 with Lipschitz coefficients in ℝⁿ. Ass
From playlist Geometry
Quantitative decompositions of Lipschitz mappings - Guy C. David
Analysis Seminar Topic: Quantitative decompositions of Lipschitz mappings Speaker: Guy C. David Affiliation: Ball State University Date: May 12, 2020 For more video please visit http://video.ias.edu
From playlist Mathematics
Introduction to Scalar Curvature and Convergence - Christina Sormani
Emerging Topics Working Group Topic: Introduction to Scalar Curvature and Convergence Speaker: Christina Sormani Affilaition: IAS Date: October 15, 2018 For more video please visit http://video.ias.edu
From playlist Mathematics
C. Sormani - Intrinsic Flat and Gromov-Hausdorff Convergence 1
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
Henry Adams (3/22/22): Gromov-Hausdorff distances, Borsuk-Ulam theorems, and Vietoris-Rips complexes
The Gromov-Hausdorff distance between two metric spaces is an important tool in geometry, but it is difficult to compute. For example, the Gromov-Hausdorff distance between unit spheres of different dimensions is unknown in nearly all cases. I will introduce recent work by Lim, Mémoli, and
From playlist Vietoris-Rips Seminar
Fitting a manifold to noisy data by Hariharan Narayanan
DISCUSSION MEETING THE THEORETICAL BASIS OF MACHINE LEARNING (ML) ORGANIZERS: Chiranjib Bhattacharya, Sunita Sarawagi, Ravi Sundaram and SVN Vishwanathan DATE : 27 December 2018 to 29 December 2018 VENUE : Ramanujan Lecture Hall, ICTS, Bangalore ML (Machine Learning) has enjoyed tr
From playlist The Theoretical Basis of Machine Learning 2018 (ML)
MAST30026 Lecture 17: Integrals
I began by explaining how, in order to work with infinite-dimensional function spaces constructively, we need to use integrals. Then I defined an "integral pair", showed that the Riemann integral on a closed interval is an example, and proved that there is a product operation on integral p
From playlist MAST30026 Metric and Hilbert spaces
Yevgeny Liokumovich (9/10/21): Urysohn width, isoperimetric inequalities and scalar curvature
There exists a positive constant c(n) with the following property. If M is a metric space, such that every ball B of radius 1 in M has Hausdorff n-dimensional measure less than c(n), then there exists a continuous map f from M to (n-1)-dimensional simplicial complex, such that every pre-im
From playlist Vietoris-Rips Seminar
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