Algebraic groups | Theorems in algebraic geometry

Chevalley's structure theorem

In algebraic geometry, Chevalley's structure theorem states that a smooth connected algebraic group over a perfect field has a unique normal smooth connected affine algebraic subgroup such that the quotient is an abelian variety. It was proved by (though he had previously announced the result in 1953), Barsotti , and . Chevalley's original proof, and the other early proofs by Barsotti and Rosenlicht, used the idea of mapping the algebraic group to its Albanese variety. The original proofs were based on Weil's book Foundations of algebraic geometry and are hard to follow for anyone unfamiliar with Weil's foundations, but later gave an exposition of Chevalley's proof in scheme-theoretic terminology. Over non-perfect fields there is still a smallest normal connected linear subgroup such that the quotient is an abelian variety, but the linear subgroup need not be smooth. A consequence of Chevalley's theorem is that any algebraic group over a field is quasi-projective. (Wikipedia).

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Theory of numbers: Chevalley-Warning theorem

This lecture is part of an online undergraduate course on the theory of numbers. We prove the Chevalley-Warning theorem, which which gives conditions for a polynomial in several variables to have a solution modulo a prime. For the other lectures in the course see https://www.youtube.

From playlist Theory of numbers

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Cayley-Hamilton Theorem Example 2

Matrix Theory: Let A be the 3x3 matrix A = [1 2 2 / 2 0 1 / 1 3 4] with entries in the field Z/5. We verify the Cayley-Hamilton Theorem for A and compute the inverse of I + A using a geometric power series.

From playlist Matrix Theory

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Heine Borel Theorem

Here I prove the Heine-Borel Theorem, one of the most fundamental theorems in analysis. It says that in R^n, all boxes must be compact. The proof itself is very neat, and uses a bisection-type argument. Enjoy! Topology Playlist: https://www.youtube.com/playlist?list=PLJb1qAQIrmmA13vj9xkHG

From playlist Topology

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Proof that Cayley table row and column entries are unique and complete

In this video I show a proof of why all the row and column entries in a Cayley table are unique and why all of the elements in the group appear in each row and column. This proof goes a long way towards proving Cayley's theorem.

From playlist Abstract algebra

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Introduction to number theory lecture 22. Chevalley-Warning theorem

This lecture is part of my Berkeley math 115 course "Introduction to number theory" For the other lectures in the course see https://www.youtube.com/playlist?list=PL8yHsr3EFj53L8sMbzIhhXSAOpuZ1Fov8 We discuss the Chevalley-Warning theorem, which says roughly that it is easy to find soluti

From playlist Introduction to number theory (Berkeley Math 115)

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Theorem 1.10 - part 10.5 - Neron-Ogg-Shafarevich - Structure of m-Torsion of A mod p

Here we use the theory of Neron Models, Chevalley-Rosenlicht, and a handful of other things to determine the structure of the torsion of an Abelian variety with bad reduction modulo p. This is used in proving the hard part of the Neron-Ogg-Shafarevich criterion: if an abelian variety has a

From playlist Theorem 1.10

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Simple grps 1 by N. S. Narasimha Sastry

DATE & TIME 05 November 2016 to 14 November 2016 VENUE Ramanujan Lecture Hall, ICTS Bangalore Computational techniques are of great help in dealing with substantial, otherwise intractable examples, possibly leading to further structural insights and the detection of patterns in many abstra

From playlist Group Theory and Computational Methods

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Cayley-Hamilton Theorem: General Case

Matrix Theory: We state and prove the Cayley-Hamilton Theorem over a general field F. That is, we show each square matrix with entries in F satisfies its characteristic polynomial. We consider the special cases of diagonal and companion matrices before giving the proof.

From playlist Matrix Theory

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Spectral and scattering features of hyperbolic manifolds - Michael Magee

Michael Magee Member, School of Mathematics October 1, 2014 More videos on http://video.ias.edu

From playlist Mathematics

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Introduction to additive combinatorics lecture 10.8 --- A weak form of Freiman's theorem

In this short video I explain how the proof of Freiman's theorem for subsets of Z differs from the proof given earlier for subsets of F_p^N. The answer is not very much: the main differences are due to the fact that cyclic groups of prime order do not have lots of subgroups, so one has to

From playlist Introduction to Additive Combinatorics (Cambridge Part III course)

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Oksana Yakimova, Research talk - 30 January 2015

Oksana Yakimova (Universität Jena) - Research talk http://www.crm.sns.it/course/4158/ On symmetric invariants of semi-direct products. Let $\mathfrak g$ be a complex reductive Lie algebra. By the Chevalley restriction theorem, the subalgebra of symmetric invariants $S(\mathfrak g)^{\math

From playlist Lie Theory and Representation Theory - 2015

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CurvesSurfaces3: De Casteljau Bezier Curves in Algebraic Calculus | N J Wildberger

We explain how to extend Archimedes' famous Parabolic Area Formula to the cubic situation. This formula was historically the first major calculation in Calculus, and gave an explicit and workable formula for the area of a slice of a parabola, cut off by a chord, in terms of the area of a p

From playlist MathSeminars

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Peter Stevenhagen: The Chebotarev density theorem

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 Jean-Morlet Chair - Shparlinski/Kohel

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Ax-Katz-Chevalley-Warning Introduction

Take a smooth projective variety defined over a finite field FF_p. The number of FF_p points is actually congruent to one modulo p and actually how divisible by p this number is has to do with the Hodge diamond.

From playlist Newton above Hodge

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PMSP - Approximate algebraic structure (groups, fields, homomorphisms, ...) II - Ben Green

Ben Green University of Cambridge June 14, 2010 For more videos, visit http://video.ias.edu

From playlist Mathematics

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Homogeneous spaces, algebraic K-theory and cohomological(...) - Izquierdo - Workshop 2 - CEB T2 2019

Diego Izquierdo (MPIM Bonn) / 24.06.2019 Homogeneous spaces, algebraic K-theory and cohomological dimension of fields. In 1986, Kato and Kuzumaki stated a set of conjectures which aimed at giving a Diophantine characterization of the cohomological dimension of fields in terms of Milnor

From playlist 2019 - T2 - Reinventing rational points

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Proof that the Sequence {1/n} is a Cauchy Sequence

Please Subscribe here, thank you!!! https://goo.gl/JQ8Nys Proof that the Sequence {1/n} is a Cauchy Sequence

From playlist Cauchy Sequences

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Plenary lecture 2 by Emmanuel Breuillard - Part 1

Geometry Topology and Dynamics in Negative Curvature URL: https://www.icts.res.in/program/gtdnc DATES: Monday 02 Aug, 2010 - Saturday 07 Aug, 2010 VENUE : Raman Research Institute, Bangalore DESCRIPTION: This is An ICM Satellite Conference. The conference intends to bring together ma

From playlist Geometry Topology and Dynamics in Negative Curvature

Related pages

Abelian variety | Albanese variety | Algebraic group | Néron–Ogg–Shafarevich criterion | Perfect field | Algebraic geometry | Generalized Jacobian