Differential structures | Geometric topology | 4-manifolds | Theorems in topology | Surgery theory
In 4-dimensional topology, a branch of mathematics, Rokhlin's theorem states that if a smooth, closed 4-manifold M has a spin structure (or, equivalently, the second Stiefel–Whitney class vanishes), then the signature of its intersection form, a quadratic form on the second cohomology group , is divisible by 16. The theorem is named for Vladimir Rokhlin, who proved it in 1952. (Wikipedia).
Dimitri Zvonkine - On two ELSV formulas
The ELSV formula (discovered by Ekedahl, Lando, Shapiro and Vainshtein) is an equality between two numbers. The first one is a Hurwitz number that can be defined as the number of factorizations of a given permutation into transpositions. The second is the integral of a characteristic class
From playlist 4th Itzykson Colloquium - Moduli Spaces and Quantum Curves
Entropy Equipartition along almost Geodesics in Negatively Curved Groups by Amos Nevo
PROGRAM : ERGODIC THEORY AND DYNAMICAL SYSTEMS (HYBRID) ORGANIZERS : C. S. Aravinda (TIFR-CAM, Bengaluru), Anish Ghosh (TIFR, Mumbai) and Riddhi Shah (JNU, New Delhi) DATE : 05 December 2022 to 16 December 2022 VENUE : Ramanujan Lecture Hall and Online The programme will have an emphasis
From playlist Ergodic Theory and Dynamical Systems 2022
Gábor Szabó: "Classification of group actions on C*-algebras"
Actions of Tensor Categories on C*-algebras 2021 Mini Course: "Classification of group actions on C*-algebras" Gábor Szabó - KU Leuven Abstract: This talk will survey the classification of group actions on C*-algebras. One can often observe a rigid behavior of suitable classes of outer a
From playlist Actions of Tensor Categories on C*-algebras 2021
Joachim Zacharias: Noncommutative covering dimension for C*-algebras and dynamical systems
(in collaboration with Hirshberg, Szabo, Winter, Wu) Various noncommutative generalisations of dimension have been considered and studies in the past decades. In recent years certain new dimension concepts for noncommutative C*-algebras, called nuclear dimension and a related dimension co
From playlist HIM Lectures: Trimester Program "Non-commutative Geometry and its Applications"
Rahim Moosa: Around Jouanolou-type theorems
Abstract: In the mid-90’s, generalising a theorem of Jouanolou, Hrushovski proved that if a D-variety over the constant field C has no non-constant D-rational functions to C, then it has only finitely many D-subvarieties of codimension one. This theorem has analogues in other geometric con
From playlist Combinatorics
Irving Dai - Homology cobordism and local equivalence between plumbed manifolds
June 22, 2018 - This talk was part of the 2018 RTG mini-conference Low-dimensional topology and its interactions with symplectic geometry Recently constructed by Hendricks and Manolescu, involutive Heegaard Floer homology provides several new tools for studying the three-dimensional homol
From playlist 2018 RTG mini-conference on low-dimensional topology and its interactions with symplectic geometry I
Topics in Combinatorics lecture 6.2 --- Variants of the Borsuk-Ulam theorem
The Borsuk-Ulam theorem states that if f is a continuous function from S^n to R^n (that is, from the n-sphere to n-dimensional Euclidean space), then there exists x such that f(x) = f(-x). It has many applications, including in combinatorics. In this video I prepare the ground for explaini
From playlist Topics in Combinatorics (Cambridge Part III course)
Yakov Sinai - The Abel Prize interview 2014
00:15 beginnings, family influences 00:55 no Olympiad success 02:00 mathematical talent 02:30 schooling (WWII, USSR) 04:20 teachers 05:35 Moscow State University (Mekh mat) 07:40 mathematics vs. mechanics 08:52 Dynkin 10:13 Kolmogorov 10:35 Gel'fand 12:31 Rokhlin, Abramov 17:25 Dynamical s
From playlist The Abel Prize Interviews
Alex SIMPSON - Probability sheaves
In [2], Tao observes that the probability theory concerns itself with properties that are \preserved with respect to extension of the underlying sample space", in much the same way that modern geometry concerns itself with properties that are invariant with respect to underlying symmetries
From playlist Topos à l'IHES
Daniel Balint: Discounting invariant FTAP for large financial markets
Abstract: For large financial markets as introduced in Kramkov and Kabanov 94, there are several existing absence-of-arbitrage conditions in the literature. They all have in common that they depend in a crucial way on the discounting factor. We introduce a new concept, generalizing NAA1 (K
From playlist Probability and Statistics
Decoupling in harmonic analysis and the Vinogradov mean value theorem - Bourgain
Topic: Decoupling in harmonic analysis and the Vinogradov mean value theorem Speaker: Jean Bourgain Date: Thursday, December 17 Based on a new decoupling inequality for curves in ℝd, we obtain the essentially optimal form of Vinogradov's mean value theorem in all dimensions (the case d=3
From playlist Mathematics
Bifurcations of chaotic attractors by Viktor Avrutin
PROGRAM DYNAMICS OF COMPLEX SYSTEMS 2018 ORGANIZERS Amit Apte, Soumitro Banerjee, Pranay Goel, Partha Guha, Neelima Gupte, Govindan Rangarajan and Somdatta Sinha DATE: 16 June 2018 to 30 June 2018 VENUE: Ramanujan hall for Summer School held from 16 - 25 June, 2018; Madhava hall for W
From playlist Dynamics of Complex systems 2018
The Quasi-Polynomial Freiman-Ruzsa Theorem of Sanders - Shachar Lovett
Shachar Lovett Institute for Advanced Study March 20, 2012 The polynomial Freiman-Ruzsa conjecture is one of the important open problems in additive combinatorics. In computer science, it already has several diverse applications: explicit constructions of two-source extractors; improved bo
From playlist Mathematics
My Favorite Theorem: The Borsuk-Ulam Theorem
Many thanks for 10k subscribers! Fun video for you from Topology: The Borsuk-Ulam Theorem. One interpretation of this is that on the surface of the earth, there must be some point where it and its antipode (the spot exactly opposite it) have the exact same temperature and pressure. More ge
From playlist Cool Math Series
Vladimir Berkovich: de Rham theorem in non-Archimedean analytic geometry
Abstract: In my work in progress on complex analytic vanishing cycles for formal schemes, I have defined integral "etale" cohomology groups of a compact strictly analytic space over the field of Laurent power series with complex coefficients. These are finitely generated abelian groups pro
From playlist Algebraic and Complex Geometry
The Stepanov Method - Avi Wigderson
Avi Wigderson Institute for Advanced Study May 25, 2010 The Stepanov method is an elementary method for proving bounds on the number of roots of polynomials. At its core is the following idea. To upper bound the number of roots of a polynomial f(x) in a field, one sets up an auxiliary pol
From playlist Mathematics
Weil conjectures 2: Functional equation
This is the second lecture about the Weil conjectures. We show that the Riemann-Roch theorem implies the rationality and functional equation of the zeta function of a curve over a finite field.
From playlist Algebraic geometry: extra topics
Calculus 1 (Stewart) Ep 22, Mean Value Theorem (Oct 28, 2021)
This is a recording of a live class for Math 1171, Calculus 1, an undergraduate course for math majors (and others) at Fairfield University, Fall 2021. The textbook is Stewart. PDF of the written notes, and a list of all episodes is at the class website. Class website: http://cstaecker.f
From playlist Math 1171 (Calculus 1) Fall 2021
Equidistribution of Unipotent Random Walks on Homogeneous spaces by Emmanuel Breuillard
PROGRAM : ERGODIC THEORY AND DYNAMICAL SYSTEMS (HYBRID) ORGANIZERS : C. S. Aravinda (TIFR-CAM, Bengaluru), Anish Ghosh (TIFR, Mumbai) and Riddhi Shah (JNU, New Delhi) DATE : 05 December 2022 to 16 December 2022 VENUE : Ramanujan Lecture Hall and Online The programme will have an emphasis
From playlist Ergodic Theory and Dynamical Systems 2022
Monotonicity of the Riemann zeta function and related functions - P Zvengrowski [2012]
General Mathematics Seminar of the St. Petersburg Division of Steklov Institute of Mathematics, Russian Academy of Sciences May 17, 2012 14:00, St. Petersburg, POMI, room 311 (27 Fontanka) Monotonicity of the Riemann zeta function and related functions P. Zvengrowski University o
From playlist Number Theory