Linear operators | Operator theory

Unbounded operator

In mathematics, more specifically functional analysis and operator theory, the notion of unbounded operator provides an abstract framework for dealing with differential operators, unbounded observables in quantum mechanics, and other cases. The term "unbounded operator" can be misleading, since * "unbounded" should sometimes be understood as "not necessarily bounded"; * "operator" should be understood as "linear operator" (as in the case of "bounded operator"); * the domain of the operator is a linear subspace, not necessarily the whole space; * this linear subspace is not necessarily closed; often (but not always) it is assumed to be dense; * in the special case of a bounded operator, still, the domain is usually assumed to be the whole space. In contrast to bounded operators, unbounded operators on a given space do not form an algebra, nor even a linear space, because each one is defined on its own domain. The term "operator" often means "bounded linear operator", but in the context of this article it means "unbounded operator", with the reservations made above. The given space is assumed to be a Hilbert space. Some generalizations to Banach spaces and more general topological vector spaces are possible. (Wikipedia).

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Unbeschränkte Operatoren

Abonniert den Kanal, damit er auch in Zukunft bestehen kann. Es ist vollkommen kostenlos und ihr werdet direkt informiert, wenn ich einen Livestream anbiete. Hier erzähle ich ein wenig über lineare Operatoren zwischen normierten Räumen (oder Hilberträumen) und gebe die wichtige Definition

From playlist Funktionalanalysis

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(ML 1.3) What is unsupervised learning?

A broad overview. A playlist of these Machine Learning videos is available here: http://www.youtube.com/my_playlists?p=D0F06AA0D2E8FFBA

From playlist Machine Learning

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(ML 11.1) Estimators

Definition of an estimator. Examples of estimators. Definition of an unbiased estimator.

From playlist Machine Learning

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Unsupervised Learning

This video is part of the Udacity course "Deep Learning". Watch the full course at https://www.udacity.com/course/ud730

From playlist Deep Learning | Udacity

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C언어 09강 연산자-II

이번 강의는 ' C언어 09강 연산자-II ' 편입니다. 바로가기: http://iotcenter.seoul.go.kr/648

From playlist c언어

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C언어 08강 연산자-I

이번 강의는 ' C언어 08강 연산자-I ' 편입니다. 바로가기 : http://iotcenter.seoul.go.kr/647

From playlist c언어

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Operator Overloading In C++ | What Is Operator Overloading In C++? | C++ Programming | Simplilearn

"This video on Operator Overloading in C++ will help you understand What is Operator Overloading in C++ and how an operator is overloaded to provide special meaning to the user-defined datatype. We'll also learn the operators which can't be overloaded, along with the types of operator ove

From playlist C++ Tutorial Videos

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Bitcoin Q&A: Unstoppable Code

Governance and the market share of Bitcoin. It drops in a cyclical way when people become temporarily disillusioned and overwhelm other altcoins with exuberant attention they weren't really prepared for. When the spotlight shifts onto you, that's when you can't stumble. The adversarial att

From playlist English Subtitles - aantonop Videos with subtitles in English

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Hermitian Operators (Self-Adjoint Operators) | Quantum Mechanics

In this video, we will talk about Hermitian operators in quantum mechanics. If an operator A is a Hermitian operator, then it is the same as its adjoint operator A-dagger, which is defined via this equation here. Usually, the terms "Hermitian" and "self adjoint" are used interchangeably, h

From playlist Quantum Mechanics, Quantum Field Theory

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Koen van den Dungen: Localisations and the Kasparov product in unbounded KK-theory

Talk by Koen van den Dungen in Global Noncommutative Geometry Seminar (Europe) http://www.noncommutativegeometry.nl/ncgseminar/ on May 19, 2021

From playlist Global Noncommutative Geometry Seminar (Europe)

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Jens Kaad: Differentiable absorption of Hilbert C*-modules

The Kasparov absorption (or stabilization) theorem states that any countably generated Hilbert C^*-module is isomorphic to a direct summand in a standard module. In this talk, I will generalize this result by incorporating a densely defined derivation on the base C^*-algebra. The extra com

From playlist HIM Lectures: Trimester Program "Non-commutative Geometry and its Applications"

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Jens Kaad: Exterior products of compact quantum metric spaces

Talk by Jens Kaad in Global Noncommutative Geometry Seminar (Europe) http://www.noncommutativegeometry.nl/ncgseminar/ on November 24, 2020.

From playlist Global Noncommutative Geometry Seminar (Europe)

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The damped wave equation with unbounded and singular damping by Petr Siegl

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From playlist Non-Hermitian Physics - PHHQP XVIII

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Lara Ismert: "Heisenberg Pairs on Hilbert C*-modules"

Actions of Tensor Categories on C*-algebras 2021 "Heisenberg Pairs on Hilbert C*-modules" Lara Ismert - Embry-Riddle Aeronautical University, Mathematics Abstract: Roughly speaking, a Heisenberg pair on a Hilbert space is a pair of self-adjoint operators (A,B) which satisfy the Heisenber

From playlist Actions of Tensor Categories on C*-algebras 2021

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Random Matrices and Their Limits - R. Speicher - Workshop 2 - CEB T3 2017

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From playlist 2017 - T3 - Analysis in Quantum Information Theory - CEB Trimester

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Kehe Zhu: Products of Toeplitz operators on the Fock space

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 Analysis and its Applications

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Christiane Tretter: New spectral bounds for damped systems

Abstract: In this talk new enclosures for the spectra of operators associated with second order Cauchy problems are presented for non-selfadjoint damping. Our new results yield much better bounds than the numerical range of these non-selfadjoint operators for both uniformly accretive and s

From playlist Analysis and its Applications

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Adjoint / Daggered Operators in Quantum Mechanics

In this video, we will explain adjoint operators in quantum mechanics. First of all, for any operator A, we can define its adjoint, A-dagger, via this equation. The idea behind this is, that while operators in quantum mechanics usually act towards the right, adjoint operators act to the le

From playlist Quantum Mechanics, Quantum Field Theory

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Bram Mesland: Noncommutative geometry of Bianchi groups

The lecture was held within the framework of the Hausdorff Trimester Program: Non-commutative Geometry and its Applications and the Workshop: Number theory and non-commutative geometry 27.11.2014

From playlist HIM Lectures: Trimester Program "Non-commutative Geometry and its Applications"

Related pages

Differential operator | Hahn–Banach theorem | Linear subspace | Functional analysis | Functional calculus | Self-adjoint operator | Riesz representation theorem | Direct sum of modules | Derivative | Continuous function | Topological vector space | Bounded operator | Banach space | Hyperplane | Algebra over a field | Sequence | Stone's theorem on one-parameter unitary groups | Hellinger–Toeplitz theorem | John von Neumann | Stone–von Neumann theorem | Linear map | Dense set | Closed range theorem | Discontinuous linear map | Mathematics | Normal operator | Function (mathematics) | Spectrum (functional analysis) | Subset | Limit of a sequence | Operator theory | Hilbert space | Interval (mathematics) | Transpose | Time evolution | Von Neumann's theorem | Graph of a function | Cayley transform | Closed set | Densely defined operator