Complex analysis | Types of functions | Subharmonic functions | Potential theory

Subharmonic function

In mathematics, subharmonic and superharmonic functions are important classes of functions used extensively in partial differential equations, complex analysis and potential theory. Intuitively, subharmonic functions are related to convex functions of one variable as follows. If the graph of a convex function and a line intersect at two points, then the graph of the convex function is below the line between those points. In the same way, if the values of a subharmonic function are no larger than the values of a harmonic function on the boundary of a ball, then the values of the subharmonic function are no larger than the values of the harmonic function also inside the ball. Superharmonic functions can be defined by the same description, only replacing "no larger" with "no smaller". Alternatively, a superharmonic function is just the negative of a subharmonic function, and for this reason any property of subharmonic functions can be easily transferred to superharmonic functions. (Wikipedia).

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Definition of a Surjective Function and a Function that is NOT Surjective

We define what it means for a function to be surjective and explain the intuition behind the definition. We then do an example where we show a function is not surjective. Surjective functions are also called onto functions. Useful Math Supplies https://amzn.to/3Y5TGcv My Recording Gear ht

From playlist Injective, Surjective, and Bijective Functions

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What is a function?

This video explains what a mathematical function is and how it defines a relationship between two sets, the domain and the range. It also introduces three important categories of function: injective, surjective and bijective.

From playlist Foundational Math

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Definition of an Injective Function and Sample Proof

We define what it means for a function to be injective and do a simple proof where we show a specific function is injective. Injective functions are also called one-to-one functions. Useful Math Supplies https://amzn.to/3Y5TGcv My Recording Gear https://amzn.to/3BFvcxp (these are my affil

From playlist Injective, Surjective, and Bijective Functions

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The Definition of a Surjective(Onto) Function and Explanation

The Definition of a Surjective(Onto) Function and Explanation

From playlist Functions, Sets, and Relations

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2022 10 Dan Coman: Extension of quasiplurisubharmonic functions

CONFERENCE Recording during the thematic meeting : "Complex Geometry, Dynamical Sytems and Foliation Theory" the October 20, 2022 at the Centre International de Rencontres Mathématiques (Marseille, France) Filmmaker: Jean Petit Find this video and other talks given by worldwide mathemat

From playlist Analysis and its Applications

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Hilbert Space Techniques in Complex Analysis and Geometry (Lecture 11) by Dror Varolin

PROGRAM CAUCHY-RIEMANN EQUATIONS IN HIGHER DIMENSIONS ORGANIZERS: Sivaguru, Diganta Borah and Debraj Chakrabarti DATE: 15 July 2019 to 02 August 2019 VENUE: Ramanujan Lecture Hall, ICTS Bangalore Complex analysis is one of the central areas of modern mathematics, and deals with holomo

From playlist Cauchy-Riemann Equations in Higher Dimensions 2019

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Trigonometric Functions: Sine, Cosine, Tangent, Cosecant, Secant, and Cotangent

Oh man, what is all this sine and cosine business? What do these things even mean?! And Greek letters now? I don't know Greek! OK friend, just relax. Understanding the trig functions is as easy as pi radians. We just make some triangles and set up a few definitions. I promise it's no sweat

From playlist Trigonometry

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Hilbert Space Techniques in Complex Analysis and Geometry (Lecture 7) by Dror Varolin

PROGRAM CAUCHY-RIEMANN EQUATIONS IN HIGHER DIMENSIONS ORGANIZERS: Sivaguru, Diganta Borah and Debraj Chakrabarti DATE: 15 July 2019 to 02 August 2019 VENUE: Ramanujan Lecture Hall, ICTS Bangalore Complex analysis is one of the central areas of modern mathematics, and deals with holomo

From playlist Cauchy-Riemann Equations in Higher Dimensions 2019

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Three-dimensionality of the Triadic Resonance Instability of a Plane by Pierre Philippe Cortet

DISCUSSION MEETING WAVES, INSTABILITIES AND MIXING IN ROTATING AND STRATIFIED FLOWS (ONLINE) ORGANIZERS: Thierry Dauxois (CNRS & ENS de Lyon, France), Sylvain Joubaud (ENS de Lyon, France), Manikandan Mathur (IIT Madras, India), Philippe Odier (ENS de Lyon, France) and Anubhab Roy (IIT M

From playlist Waves, Instabilities and Mixing in Rotating and Stratified Flows (ONLINE)

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What is an Injective Function? Definition and Explanation

An explanation to help understand what it means for a function to be injective, also known as one-to-one. The definition of an injection leads us to some important properties of injective functions! Subscribe to see more new math videos! Music: OcularNebula - The Lopez

From playlist Functions

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Injective, Surjective and Bijective Functions (continued)

This video is the second part of an introduction to the basic concepts of functions. It looks at the different ways of representing injective, surjective and bijective functions. Along the way I describe a neat way to arrive at the graphical representation of a function.

From playlist Foundational Math

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Introduction to Hyperbolic Functions

This video provides a basic overview of hyperbolic function. The lesson defines the hyperbolic functions, shows the graphs of the hyperbolic functions, and gives the properties of hyperbolic functions.

From playlist Using the Properties of Hyperbolic Functions

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Mohan Ramachandran

https://www.math.ias.edu/files/media/agenda.pdf More videos on http://video.ias.edu

From playlist Mathematics

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Hilbert Space Techniques in Complex Analysis and Geometry (Lecture 9) by Dror Varolin

PROGRAM CAUCHY-RIEMANN EQUATIONS IN HIGHER DIMENSIONS ORGANIZERS: Sivaguru, Diganta Borah and Debraj Chakrabarti DATE: 15 July 2019 to 02 August 2019 VENUE: Ramanujan Lecture Hall, ICTS Bangalore Complex analysis is one of the central areas of modern mathematics, and deals with holomo

From playlist Cauchy-Riemann Equations in Higher Dimensions 2019

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Kai Cieliebak - Stein and Weinstein manifolds

Stein manifolds arise naturally in the theory of several complex variables. This talk will give an informal introduction to some of their topological and symplectic aspects such as: handlebody construction of Stein manifolds; their symplectic counterparts; Weinstein manifolds; flexibility

From playlist Not Only Scalar Curvature Seminar

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Abstract Algebra | Surjective Functions

We give the definition of a surjective function, an outline for proving that a function is surjective, and some examples. http://www.michael-penn.net http://www.randolphcollege.edu/mathematics/

From playlist Abstract Algebra

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Dror Varolin - Minicourse - Lecture 3

Dror Varolin Variations of Holomorphic Hilbert spaces Traditional complex analysis focuses on a single space, like a domain in Euclidean space, or more generally a complex manifold, and studies holomorphic maps on that space, into some target space. The typical target space for a domain i

From playlist Maryland Analysis and Geometry Atelier

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Hilbert Space Techniques in Complex Analysis and Geometry (Lecture 10) by Dror Varolin

PROGRAM CAUCHY-RIEMANN EQUATIONS IN HIGHER DIMENSIONS ORGANIZERS: Sivaguru, Diganta Borah and Debraj Chakrabarti DATE: 15 July 2019 to 02 August 2019 VENUE: Ramanujan Lecture Hall, ICTS Bangalore Complex analysis is one of the central areas of modern mathematics, and deals with holomo

From playlist Cauchy-Riemann Equations in Higher Dimensions 2019

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How to use the Subtotal Feature and the SUBTOTAL Function in Excel

Sign up for our Excel webinar, times added weekly: https://www.excelcampus.com/blueprint-registration/ In this video, discover the difference between the SUBTOTAL function and the Subtotal feature in Excel and learn how to use both to insert subtotals in your data. Here is a link to the

From playlist Formulas & Functions

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Fine topology (potential theory) | Convex function | Poisson kernel | Plurisubharmonic function | If and only if | Complex analysis | Convex cone | Continuous function | Potential theory | Additive inverse | Maximum principle | Boundary (topology) | Maxima and minima | Ball (mathematics) | Mathematics | Function (mathematics) | Real number | Riemannian manifold | Euclidean space | Semi-continuity | Arithmetic mean | Holomorphic function | Harmonic function | Interior (topology) | Analytic function | Dominated convergence theorem | Lp space | Graph of a function | Laplace–Beltrami operator | Borel measure | Open set | Hardy–Littlewood maximal function