(ML 19.5) Positive semidefinite kernels (Covariance functions)
Definition of a positive semidefinite kernel, or covariance function. A simple example. Explanation of terminology: autocovariance, positive definite kernel, stationary kernel, isotropic kernel, covariogram, positive definite function.
From playlist Machine Learning
Inner & Outer Semidirect Products Derivation - Group Theory
Semidirect products are a very important tool for studying groups because they allow us to break a group into smaller components using normal subgroups and complements! Here we describe a derivation for the idea of semidirect products and an explanation of how the map into the automorphism
From playlist Group Theory
Product Rules in Semidefinite Programming - Rajat Mittal
Rajat Mittal March 22, 2010 Semidefinite programming bounds are widely used in combinatorial optimization, quantum computing and complexity theory. The first semidefinite programming bound to gain fame is the so-called theta number developed by Lov\'asz to compute the Shannon capacity of
From playlist Mathematics
Semiclassical Eigenfunction Estimates - Melissa Tacy
Semiclassical Eigenfunction Estimates - Melissa Tacy Institute for Advanced Study October 29, 2010 ANALYSIS/MATHEMATICAL PHYSICS SEMINAR Concentration phenomena for Laplacian eigenfunctions can be studied by obtaining estimates for their LpLp growth. By considering eigenfunctions as quasi
From playlist Mathematics
An incredible semicircle problem!
A semicircle contains an inscribed semicircle dividing its diameter into two lengths a and b. Can you find the formula for the inscribed semicircle's diameter in terms of the lengths a and b? What is the locus of the center of the inscribed semicircle? Thanks to Nick from Greece for the su
From playlist Math Puzzles, Riddles And Brain Teasers
Joachim Cuntz: Semigroup C*-algebras and toric varieties
The lecture was held within the framework of the Hausdorff Trimester Program: K-Theory and Related Fields. The coordinate ring of a toric variety is the semigroup ring of a finitely generated subsemigroup of Zn. Such semigroups have the interesting feature that their family of constructib
From playlist HIM Lectures: Trimester Program "K-Theory and Related Fields"
Semi-coarse Spaces, Homotopy [Jonathan Treviño-Marroquín]
Semi-coarse spaces is an alternative to study (undirected) graphs through large-scale geometry. In this video, we present the structure and a homotopy what we worked on. In the final part, we look at the fundamental homotopy group of cyclic graphs.
From playlist Contributed Videos
How To Calculate The Perimeter of a Semicircle
This video explains how to calculate the perimeter of a semicircle given the radius and diameter in two separate practice problems.
From playlist Pre-Algebra Video Playlist
Various Approaches to Semiclassical Quantum Dynamics - George A. Hagedorn
George A. Hagedorn Virginia Tech March 6, 2012 I shall describe several techniques for finding approximate solutions to the time-dependent Schr\"odinger equation in the semiclassical limit. The first of these involves expansions in "semiclassical wave packets" that are also sometimes calle
From playlist Mathematics
André Martinez : Estimates on the molecular dynamics for the predissociation process
Abstract: We study the survival probability associated with a semiclassical matrix Schrödinger operator that models the predissociation of a general molecule in the Born-Oppenheimer approximation. We show that it is given by its usual time-dependent exponential contribution, up to a remind
From playlist Mathematical Physics