Curves | Projective geometry | Differential geometry

Dual curve

In projective geometry, a dual curve of a given plane curve C is a curve in the dual projective plane consisting of the set of lines tangent to C. There is a map from a curve to its dual, sending each point to the point dual to its tangent line. If C is algebraic then so is its dual and the degree of the dual is known as the class of the original curve. The equation of the dual of C, given in line coordinates, is known as the tangential equation of C. Duality is an involution: the dual of the dual of C is the original curve C. The construction of the dual curve is the geometrical underpinning for the Legendre transformation in the context of Hamiltonian mechanics. (Wikipedia).

Dual curve
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What are parallel lines and a transversal

👉 Learn about converse theorems of parallel lines and a transversal. Two lines are said to be parallel when they have the same slope and are drawn straight to each other such that they cannot meet. In geometry, parallel lines are identified by two arrow heads or two small lines indicated i

From playlist Parallel Lines and a Transversal

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What is the Alternate Exterior Angle Converse Theorem

👉 Learn about converse theorems of parallel lines and a transversal. Two lines are said to be parallel when they have the same slope and are drawn straight to each other such that they cannot meet. In geometry, parallel lines are identified by two arrow heads or two small lines indicated i

From playlist Parallel Lines and a Transversal

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What are the Angle Relationships for Parallel Lines and a Transversal

👉 Learn about converse theorems of parallel lines and a transversal. Two lines are said to be parallel when they have the same slope and are drawn straight to each other such that they cannot meet. In geometry, parallel lines are identified by two arrow heads or two small lines indicated i

From playlist Parallel Lines and a Transversal

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Proving Parallel Lines with Angle Relationships

👉 Learn about converse theorems of parallel lines and a transversal. Two lines are said to be parallel when they have the same slope and are drawn straight to each other such that they cannot meet. In geometry, parallel lines are identified by two arrow heads or two small lines indicated i

From playlist Parallel Lines and a Transversal

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What is the Alternate Interior Angle Converse Theorem

👉 Learn about converse theorems of parallel lines and a transversal. Two lines are said to be parallel when they have the same slope and are drawn straight to each other such that they cannot meet. In geometry, parallel lines are identified by two arrow heads or two small lines indicated i

From playlist Parallel Lines and a Transversal

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What is the Consecutive Interior Angle Converse Theorem

👉 Learn about converse theorems of parallel lines and a transversal. Two lines are said to be parallel when they have the same slope and are drawn straight to each other such that they cannot meet. In geometry, parallel lines are identified by two arrow heads or two small lines indicated i

From playlist Parallel Lines and a Transversal

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How To Determine If Two Lines are Parallel to Apply Angle Theorems

👉 Learn about converse theorems of parallel lines and a transversal. Two lines are said to be parallel when they have the same slope and are drawn straight to each other such that they cannot meet. In geometry, parallel lines are identified by two arrow heads or two small lines indicated i

From playlist Parallel Lines and a Transversal

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Dual basis

Dual basis definition and proof that it's a basis In this video, given a basis beta of a vector space V, I define the dual basis beta* of V*, and show that it's indeed a basis. We'll see many more applications of this concept later on, but this video already shows that it's straightforwar

From playlist Dual Spaces

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What is the Corresponding Angle Converse Theorem

👉 Learn about converse theorems of parallel lines and a transversal. Two lines are said to be parallel when they have the same slope and are drawn straight to each other such that they cannot meet. In geometry, parallel lines are identified by two arrow heads or two small lines indicated i

From playlist Parallel Lines and a Transversal

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Elliptic Curves - Lecture 10c - The dual isogeny

This video is part of a graduate course on elliptic curves that I taught at UConn in Spring 2021. The course is an introduction to the theory of elliptic curves. More information about the course can be found at the course website: https://alozano.clas.uconn.edu/math5020-elliptic-curves/

From playlist An Introduction to the Arithmetic of Elliptic Curves

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Mirror symmetry & Looijenga's conjecture - Philip Engel

Philip Engel Columbia University October 29, 2014 A cusp singularity is an isolated surface singularity whose minimal resolution is a cycle of smooth rational curves meeting transversely. Cusp singularities come in naturally dual pairs. In the 1980's Looijenga conjectured that a cusp sing

From playlist Mathematics

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Algebraic curves, tropical geometry, and moduli - Sam Payne

Sam Payne Yale University February 11, 2015 Tropical geometry gives a new approach to understanding old questions about algebraic curves and their moduli spaces, synthesizing techniques that range from Berkovich spaces to elementary combinatorics. I will discuss an outline of this method,

From playlist Mathematics

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Developments in 4-manifold topology arising from a theorem of Donaldson's - John Morgan [2017]

slides for this talk: https://drive.google.com/file/d/1_wHviPab9klzwE4UkCOvVecyopxDsZA3/view?usp=sharing Name: John Morgan Event: Workshop: Geometry of Manifolds Event URL: view webpage Title: Developments in 4-manifold topology arising from a theorem of Donaldson's Date: 2017-10-23 @9:3

From playlist Mathematics

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Jeff Erickson - Lecture 2 - Two-dimensional computational topology - 19/06/18

School on Low-Dimensional Geometry and Topology: Discrete and Algorithmic Aspects (http://geomschool2018.univ-mlv.fr/) Jeff Erickson (University of Illinois at Urbana-Champaign, USA) Two-dimensional computational topology - Lecture 2 Abstract: This series of lectures will describe recent

From playlist Jeff Erickson - School on Low-Dimensional Geometry and Topology: Discrete and Algorithmic Aspects

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What is a Manifold? Lesson 11: The Cotangent Space

What is a Manifold? Lesson 11: The Cotangent Space I have annotated an obvious error at 2:00. However annotations are not visible on mobile devices!

From playlist What is a Manifold?

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What is General Relativity? Lesson 13 Some important CFREE relations

We prove some critical CFREE expressions required for the derivation of the metric connection. Errata: At 46:00 the argument should have the vector "Z" not the vector "X". X is part of the example tensor and Z is being fed to the tensor.

From playlist What is General Relativity?

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Ciro Ciliberto, Enumeration in geometry - 15 Novembre 2017

https://www.sns.it/eventi/enumeration-geometry Colloqui della Classe di Scienze Ciro Ciliberto, Università di Roma “Tor Vergata” Enumeration in geometry Abstract: Enumeration of geometric objects verifying some specific properties is an old and venerable subject. In this talk I will

From playlist Colloqui della Classe di Scienze

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Every basis is a dual basis

In this video, I show a very neat result about dual spaces: Namely, any basis of V* is automatically a dual basis of some basis of V. Even though this result is very interesting, it's the proof that makes this very exciting, by simply using the fact that V and V** are 'very' isomorphic. En

From playlist Dual Spaces

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Mirror symmetry from the SYZ base - Benjamin Gammage

Joint IAS/Princeton University Symplectic Geometry Seminar Topic: Mirror symmetry from the SYZ base Speaker: Benjamin Gammage Affiliation: Harvard University Date: October 25, 2021

From playlist Mathematics

Related pages

Duality (projective geometry) | Tangent space | Hamiltonian mechanics | Polar curve | Inflection point | Line coordinates | Map (mathematics) | Dual cone and polar cone | Hyperplane | Gauss map | Parametric equation | Hypersurface | Homogeneous coordinates | Inverse curve | Plücker formula | Cusp (singularity) | Pedal curve | Involution (mathematics) | Convex conjugate | Cross product | Legendre transformation | Algebraic curve | Singular point of a curve | Projective geometry | Projective plane | Conic section | Tangent | Plane curve