Model theory | Field (mathematics)

Pseudo-finite field

In mathematics, a pseudo-finite field F is an infinite model of the first-order theory of finite fields. This is equivalent to the condition that F is quasi-finite (perfect with a unique extension of every positive degree) and pseudo algebraically closed (every absolutely irreducible variety over F has a point defined over F). Every hyperfinite field is pseudo-finite and every pseudo-finite field is quasifinite. Every non-principal ultraproduct of finite fields is pseudo-finite. Pseudo-finite fields were introduced by Ax. (Wikipedia).

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What is a field ?

Definition of a Field In this video, I define the concept of a field, which is basically any set where you can add, subtract, add, and divide things. Then I show some neat properties that have to be true in fields. Enjoy! What is an Ordered Field: https://youtu.be/6mc5E6x7FMQ Check out

From playlist Real Numbers

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Dugald Macpherson: Pseudofinite groups I

The lecture was held within the framework of the Hausdorff Trimester Program: Logic and Algorithms in Group Theory. Abstract: An infinite group is pseudofinite if it has the 'finite model property' – that is, if every sentence of first order logic which is true of it is also true of some

From playlist HIM Lectures: Trimester Program "Logic and Algorithms in Group Theory"

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Dugald Macpherson: Pseudofinite groups III

The lecture was held within the framework of the Hausdorff Trimester Program: Logic and Algorithms in Group Theory. Abstract: An infinite group is pseudofinite if it has the 'finite model property' – that is, if every sentence of first order logic which is true of it is also true of some

From playlist HIM Lectures: Trimester Program "Logic and Algorithms in Group Theory"

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Dugald Macpherson: Pseudofinite groups II

The lecture was held within the framework of the Hausdorff Trimester Program: Logic and Algorithms in Group Theory. Abstract: An infinite group is pseudofinite if it has the 'finite model property' – that is, if every sentence of first order logic which is true of it is also true of some

From playlist HIM Lectures: Trimester Program "Logic and Algorithms in Group Theory"

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Field Theory: Definition/ Axioms

This video is about the basics axioms of fields.

From playlist Basics: Field Theory

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Field Theory: Extensions

This video is about extensions of fields.

From playlist Basics: Field Theory

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Algebraic and Transcendental Elements; Finite Extensions - Field Theory - Lecture 01

In this video we introduce the notion of algebraic and transcendental. We then introduce a notion of "finite extension" which will help us prove every element in an extension is algebraic. See @MatthewSalomone's Abstract Algebra 2 videos. They complement this presentation with better exa

From playlist Field Theory

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Moduli of Representations and Pseudorepresentations - Carl Wang Erickson

Carl Wang Erickson Harvard University May 2, 2013 A continuous representation of a profinite group induces a continuous pseudorepresentation, where a pseudorepresentation is the data of the characteristic polynomial coefficients. We discuss the geometry of the resulting map from the moduli

From playlist Mathematics

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John s. Wilson - Metric ultraproducts of finite simple groups

John S. Wilson (University of Oxford, England) Metric ultraproducts of structures have arisen in a variety of contexts. The study of the case when the structures are finite groups is recent and motivated partly by the connection with sofic groups. We report on current joint work with An

From playlist T1-2014 : Random walks and asymptopic geometry of groups.

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Tamagawa Numbers of Linear Algebraic Groups over (...) - Rosengarten - Workshop 2 - CEB T2 2019

Zev Rosengarten (Hebrew University of Jerusalem) / 26.06.2019 Tamagawa Numbers of Linear Algebraic Groups over Function Fields In 1981, Sansuc obtained a formula for Tamagawa numbers of reductive groups over number fields, modulo some then unknown results on the arithmetic of simply con

From playlist 2019 - T2 - Reinventing rational points

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Ariyan Javanpeykar: Arithmetic and algebraic hyperbolicity

Abstract: The Green-Griffiths-Lang-Vojta conjectures relate the hyperbolicity of an algebraic variety to the finiteness of sets of “rational points”. For instance, it suggests a striking answer to the fundamental question “Why do some polynomial equations with integer coefficients have onl

From playlist Algebraic and Complex Geometry

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Local (\ell = p) Galois Deformation Rings - Ashwin Iyengar

Joint IAS/Princeton University Number Theory Seminar Topic: Local (\ell = p) Galois Deformation Rings Speaker: Ashwin Iyengar Affiliation: Johns Hopkins University Date: February 10, 2022 I will present joint work with V. Paškūnas and G. Böckle concerning deformation rings for mod p Galo

From playlist Mathematics

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Iwasawa theory of the fine Selmer groups of Galois representations by Sujatha Ramdorai

PERFECTOID SPACES ORGANIZERS: Debargha Banerjee, Denis Benois, Chitrabhanu Chaudhuri, and Narasimha Kumar Cheraku DATE & TIME: 09 September 2019 to 20 September 2019 VENUE: Madhava Lecture Hall, ICTS, Bangalore Scientific committee: Jacques Tilouine (University of Paris, France) Eknath

From playlist Perfectoid Spaces 2019

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Bjorn Poonen, Heuristics for the arithmetic of elliptic curves

VaNTAGe seminar on Sep 1, 2020. License: CC-BY-NC-SA. Closed captions provided by Brian Reinhart.

From playlist Rational points on elliptic curves

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Moduli Stacks of Galois Representations by Mathew Emerton

Program Recent developments around p-adic modular forms (ONLINE) ORGANIZERS: Debargha Banerjee (IISER Pune, India) and Denis Benois (University of Bordeaux, France) DATE: 30 November 2020 to 04 December 2020 VENUE: Online This is a follow up of the conference organized last year arou

From playlist Recent Developments Around P-adic Modular Forms (Online)

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Pseudo-reductive groups by Brian Conrad

PROGRAM ZARISKI-DENSE SUBGROUPS AND NUMBER-THEORETIC TECHNIQUES IN LIE GROUPS AND GEOMETRY (ONLINE) ORGANIZERS: Gopal Prasad, Andrei Rapinchuk, B. Sury and Aleksy Tralle DATE: 30 July 2020 VENUE: Online Unfortunately, the program was cancelled due to the COVID-19 situation but it will

From playlist Zariski-dense Subgroups and Number-theoretic Techniques in Lie Groups and Geometry (Online)

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Bjorn Poonen: Heuristics for boundedness of ranks of elliptic curves

Abstract: We present heuristics that suggest that there is a uniform bound on the rank of E(ℚ) as E varies over all elliptic curves over ℚ. This is joint work with Jennifer Park, John Voight, and Melanie Matchett Wood. Recording during the thematic meeting : "Rational Points and Algebraic

From playlist Algebraic and Complex Geometry

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Field Theory - Algebraically Closed Fields - Lecture 9

In this video we define what an algebraically closed field and assert without proof that they exist. We also explain why if you can find a single root for any polynomial, then you can find them all.

From playlist Field Theory

Related pages

Field extension | Theory (mathematical logic) | Finite field | Ultraproduct | First-order logic | Quasi-finite field