Descriptive set theory | Determinacy

Homogeneous tree

In descriptive set theory, a tree over a product set is said to be homogeneous if there is a system of measures such that the following conditions hold: * is a countably-additive measure on . * The measures are in some sense compatible under restriction of sequences: if , then . * If is in the projection of , the ultrapower by is wellfounded. An equivalent definition is produced when the final condition is replaced with the following: * There are such that if is in the projection of and , then there is such that . This condition can be thought of as a sort of countable completeness condition on the system of measures. is said to be -homogeneous if each is -complete. Homogeneous trees are involved in Martin and Steel's proof of projective determinacy. (Wikipedia).

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Morphing Symmetric Binary Trees (visual calming for anxiety; bilateral stimulation)

A symmetric binary tree is obtained by applying certain affine linear transformations recursively to the leaves starting with a trunk of unit length. This video shows six different scale factors and morphs between various angles of rotation. The animation is set to Bilateral music to help

From playlist Fractals

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Introduction to Spanning Trees

This video introduces spanning trees. mathispower4u.com

From playlist Graph Theory (Discrete Math)

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Morphing symmetric binary branching tree

A symmetric binary tree is obtained by applying certain affine linear transformations recursively to the leaves starting with a trunk of unit length. This video shows a scale factor given by the golden ratio (well, roughly 0.618) and morphs between various angles of rotation. To build yo

From playlist Fractals

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Data structures: Binary Tree

See complete series on data structures here: http://www.youtube.com/playlist?list=PL2_aWCzGMAwI3W_JlcBbtYTwiQSsOTa6P In this lesson, we have discussed binary tree in detail. We have talked about different types of binary tree like "complete binary tree", "perfect binary tree" and "balance

From playlist Data structures

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Symmetric Binary Trees (visual construction)

In this video, we see how to change use two parameters (scale factor and angle of rotation) to create various symmetric binary trees. We show five different examples of such trees (up to level 13). Choose your own parameters and create your own! Check out these videos for related construc

From playlist Fractals

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Bilateral Stimulation with Binary Symmetric Trees (visual calming for anxiety)

This video shows ten different symmetric binary trees obtained by applying certain affine linear transformations recursively to the leaves starting with a trunk of unit length. The animation is set to Bilateral music to help some people feel calm while enjoying the beauty and wonder of the

From playlist Fractals

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Binary tree mobile

This shows a 3d printed mobile produced using shapeways.com. This is joint work with Marco Mahler. This is available at http://shpws.me/nPh7.

From playlist 3D printing

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Binary Tree 1. Constructing a tree (algorithm and pseudocode)

This is the first in a series of videos about binary trees. It is an explanation of the dynamic data structure known as the Binary Tree. It describes the way in which a binary tree is constructed, and how it can be represented numerically using a system of left and right pointers. This v

From playlist Data Structures

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Identifying Isomorphic Trees | Graph Theory

Identifying and encoding isomorphic trees Algorithms repository: https://github.com/williamfiset/algorithms#tree-algorithms Video slides: https://github.com/williamfiset/Algorithms/tree/master/slides Video source code: https://github.com/williamfiset/Algorithms/tree/master/com/williamfi

From playlist Tree Algorithms

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On finite dimensional omega-categorical structures (...) - P. Simon - Workshop 1 - CEB T1 2018

Pierre Simon (Berkeley) / 31.01.2018 On finite dimensional omega-categorical structures and NIP theories The study of omega-categorical structures lies at the intersection of model theory, combinatorics and group theory. Some classes of omega-categorical structures have been classified,

From playlist 2018 - T1 - Model Theory, Combinatorics and Valued fields

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11. Learning: Identification Trees, Disorder

MIT 6.034 Artificial Intelligence, Fall 2010 View the complete course: http://ocw.mit.edu/6-034F10 Instructor: Patrick Winston In this lecture, we build an identification tree based on yes/no tests. We start by arranging the tree based on tests that result in homogeneous subsets. For la

From playlist MIT 6.034 Artificial Intelligence, Fall 2010

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Jiacheng Zhang (Princeton) -- Local equations for continuous Gibbs measures on regular trees

In this work, we localize a countable system of interacting stochastic dierential equations driven by independent Brownian motions and indexed by the vertices of a locally nite graph G = (V;E). We establish a one-to-one corespondence between the stationary interacting stochastic system and

From playlist Northeastern Probability Seminar 2020

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Felix Otto: The structure group revisited

CIRM VIRTUAL EVENT Recorded during the meeting "Pathwise Stochastic Analysis and Applications" the March 09, 2021 by the Centre International de Rencontres Mathématiques (Marseille, France) Filmmaker: Guillaume Hennenfent Find this video and other talks given by worldwide mathematician

From playlist Virtual Conference

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Spatial Events: Spatial Statistics

Spatial point patterns are collections of randomly positioned events in space. Examples include trees in a forest, positions of stars, earthquakes, crime locations, animal sightings, etc. Spatial point data analysis, as a statistical exploration of point patterns, aims to answer questions

From playlist Wolfram Technology Conference 2021

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Lionel Mason (University of Oxford) - From Twistors to Gravitational Scattering (2/2)

This lecture will obtain a compact twistor formula for the full tree-level gravitational S-matrix beyond the self-dual sector. It uses an extension of the complex geometry of twistor space of the previous lecture. In the final formula, all integrations are saturated against delta functio

From playlist Balzan Lectures

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Pablo Linares & Markus Tempelmayr - A tree-free construction of the structure group

We present a new approach to regularity structures, and in particular to the construction of the structure group, which replaces the tree-based framework of Hairer by a more Lie-geometric setting. We consider the space of pairs (a,p), where a is a placeholder for the nonlinearity and p is

From playlist Research Spotlight

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David Wiedemann: Homogenisation of processes in porous media with evolving microstructure

Many processes in porous media can cause a change of the microstructure, which can affect strongly the effective material properties as for instance the permeability. In order to derive mathematically effective models, we transform the problem from the evolving domain into a substitute pro

From playlist "SPP meets TP": Variational methods for complex phenomena in solids

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Veronika Ročková: Bayesian Spatial Adaptation

CIRM VIRTUAL EVENT Recorded during the meeting "Mathematical Methods of Modern Statistics 2" the June 09, 2020 by the Centre International de Rencontres Mathématiques (Marseille, France) Filmmaker: Guillaume Hennenfent Find this video and other talks given by worldwide mathematicians

From playlist Virtual Conference

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Log-concave polynomials in theory and applications - Cynthia Vinzant

Computer Science/Discrete Mathematics Seminar II Topic: Log-concave polynomials in theory and applications Speaker: Cynthia Vinzant Affiliation: Member, School of Mathematics Date: January 26, 2021 For more video please visit http://video.ias.edu

From playlist Mathematics

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Tree Graphs - Intro to Algorithms

This video is part of an online course, Intro to Algorithms. Check out the course here: https://www.udacity.com/course/cs215.

From playlist Introduction to Algorithms

Related pages

Descriptive set theory | Tree (descriptive set theory) | Ultrafilter | Ultraproduct | Measure (mathematics)