- Видео 97
- Просмотров 14 702
Igor Khavkine
Добавлен 20 май 2010
Algebraic topology of some embedded flag submanifolds--J. Knesel (Charles University) PHK 18.12.2024
Title: Representation theory, Schubert calculus and algebraic topology of some embedded flag submanifolds
Speaker: Jakub Knesel (Charles University)
Abstract:
In this talk we provide a representation-theoretical approach to computing characteristic classes of normal bundles of embeddings of real, complex and quaternionic Grassmannians, with the use of Schubert calculus, namely the Pieri formula. A consequence of these calculations is an alternative recursive way of computing characteristic classes of tangent bundles of Grassmannians.
Talk given at the Prague-Hradec Králové seminar on Cohomology in algebra, geometry, physics and statistics:
www.math.cas.cz/index.php/events/event/3851
researchsem...
Speaker: Jakub Knesel (Charles University)
Abstract:
In this talk we provide a representation-theoretical approach to computing characteristic classes of normal bundles of embeddings of real, complex and quaternionic Grassmannians, with the use of Schubert calculus, namely the Pieri formula. A consequence of these calculations is an alternative recursive way of computing characteristic classes of tangent bundles of Grassmannians.
Talk given at the Prague-Hradec Králové seminar on Cohomology in algebra, geometry, physics and statistics:
www.math.cas.cz/index.php/events/event/3851
researchsem...
Просмотров: 34
Видео
Interactions between contact topology, Riemannian geom...--W. Kepplinger (U. Vienna) PHK 11.12.2024
Просмотров 4721 день назад
Title: Interactions between contact topology, Riemannian geometry, and spectral theory Speaker: Willi Kepplinger (University of Vienna) Abstract: It has long been recognized that there should be ''good ways'' of using Riemannian geometry in order to make progress in contact topology. In the first place, Riemannian geometry in general and geometric analysis in particular have had an incredible i...
Lagrangian concordance is not a partial order -- Roman Golovko (Charles University) PHK 04.12.2024
Просмотров 31Месяц назад
Title: Lagrangian concordance is not a partial order Speaker: Roman Golovko (Charles University) Abstract: We will show that Lagrangian concordance between Legendrian submanifolds is not anti-symmetric, and hence does not define a partial order. Partially it is based on joint work with Georgios Dimitroglou Rizell. Talk given at the Prague-Hradec Králové seminar on Cohomology in algebra, geometr...
Homological reduction of Poisson structures -- Pedro H. Carvalho (Hradec Kralove) PHK 20.11.2024
Просмотров 99Месяц назад
Title: Homological reduction of Poisson structures Speaker: Pedro H. Carvalho (University of Hradec Kralove) Abstract: From Roytenberg-Ševera, we know that Poisson manifolds are in one-to-one correspondence with symplectic NQ-manifolds of degree one. Cattaneo-Zambon further extended this relation to the level of reduction with their graded geometric approach to Poisson reduction. Based on these...
Conformally homogeneous Lorentzian spaces -- Anton Galaev (Hradec Kralove) PHK 20.11.2024
Просмотров 54Месяц назад
Title: Conformally homogeneous Lorentzian spaces Speaker: Anton Galaev (University of Hradec Kralove) Abstract: This is a joint work with Dmitri Alekseevsky. We prove that if a simply connected non-conformally flat conformal Lorentzian manifold $(M,c)$ admits an essential transitive group of conformal transformations, then there exists a metric $g\in c$ such that $(M,g)$ is a complete homogeneo...
On Chern-Losik class for codimension two foliations -- Yaroslav Bazaikin ( nad Labem) PHK 13.11.2024
Просмотров 36Месяц назад
Title: On Chern-Losik class for codimension two foliations Speaker: Yaroslav Bazaikin (Jan Evangelista Purkyně University in Ústí nad Labem) Abstract: Losik classes generalize characteristic classes of foliations using Gelfand-Fuchs cohomology approach. The Chern-Losik class for foliations of codimension one was constructed by Losik, and he also showed the non-triviality of this class for a fol...
Combinatorics on Words in Isabelle/HOL -- Štěpán Holub (Charles University) PHK 30.10.2024
Просмотров 302 месяца назад
Title: Combinatorics on Words in Isabelle/HOL Speaker: Štěpán Holub (Charles University) Abstract: The talk will present the ongoing project of formalization of combinatorics on words in the computer proof assistant Isabelle/HOL. Independently of the particular formalized topic, the talk will attempt to serve as an introduction to Isabelle/HOL for beginners. Talk given at the Prague-Hradec Král...
Shadowing of actions of hyperbolic groups on their boundaries -- Michal Doucha (ASCR) PHK 16.10.2024
Просмотров 362 месяца назад
Title: Shadowing of actions of hyperbolic groups on their boundaries Speaker: Michal Doucha (Institute of Mathematics of ASCR) Abstract: I will give a quick introduction to general Gromov hyperbolic metric spaces, in particular hyperbolic groups, and their boundaries. A very useful way of studying hyperbolic groups is via their canonical actions on their boundaries. I will discuss a very recent...
Graded geometry of local gauge theories -- Maxim Grigoriev (Moscow S.U., Mons U.) PHK 09.10.2024
Просмотров 292 месяца назад
Title: Graded geometry of local gauge theories Speaker: Maxim Grigoriev (Moscow State University and Mons University) Abstract: Gauge PDEs generalize AKSZ sigma models to the case of general local gauge theories. Despite being very flexible and invariant these geometrical objects are usually infinite-dimensional and are difficult to define explicitly, just like standard infinitely-prolonged PDE...
Graded super Hopf algebroids -- Alexei Kotov (University of Hradec Kralove) PHK 02.10.2024
Просмотров 532 месяца назад
Title: Graded super Hopf algebroids Speaker: Alexei Kotov (University of Hradec Kralove) Abstract: The talk will be focused on Hopf algebras and algebroids in the category of Z-graded varieties. The theory of Harish-Chandra pairs will be briefly discussed and their generalization to action algebroids will be presented. Talk given at the Prague-Hradec Králové seminar on Cohomology in algebra, ge...
On nearly parallel G_2-manifolds -- Alexei Kovalev (Cambridge) PHK 29.05.2024
Просмотров 717 месяцев назад
Title: On nearly parallel G_2-manifolds Speaker: Alexei Kovalev (Cambridge) Abstract: A nearly parallel $G_2$-structure on a 7-manifold can be given by a 3-form $\phi$ of special algebraic type satisfying a differential equation $d\phi = \tau^* \phi$ for a non-zero constant $\tau$. We consider nearly parallel $G_2$-structures on the Aloff Wallach spaces and on regular Sasaki Einstein 7-manifold...
Orbifold constructions of Sasakian structures on SB mflds--A Tralle (Warmia & Mazury) PHK 22.05.2024
Просмотров 177 месяцев назад
Title: Orbifold constructions of Sasakian structures on Smale-Barden manifolds Speaker: Aleksy Tralle (University of Warmia and Mazury) Abstract: Talk given at the Prague-Hradec Králové seminar on Cohomology in algebra, geometry, physics and statistics: www.math.cas.cz/index.php/events/event/3696 researchseminars.org/talk/PHK-cohomology-seminar/104/
An introduction to the classification of C*-algebras -- Karen Strung (IM, ASCR) PHK 24.04.2024
Просмотров 1488 месяцев назад
Title: An introduction to the classification of C*-algebras Speaker: Karen Strung (Institute of Mathematics of ASCR) Abstract: I will give an expository talk about the C*-algebra classification program. In recent years, the following classification theorem was established after years of work by many authors: Theorem: Let A and B be simple, separable, nuclear C*-algebras which tracially absorb t...
The neighborhood of a leaf of a singular foliation -- C. Laurent-Gengoux (Lorraine) PHK 03.04.2024
Просмотров 489 месяцев назад
Title: The neighborhood of a leaf of a singular foliation Speaker: Camille Laurent-Gengoux (Université de Lorraine, IECL) Abstract: Near a leaf, regular foliations are classified by their monodromies. What about the singular leaves of singular foliations? The first point is that for a singular leaf, there is a transverse singular foliation, which is constant all along the leaf. In a previous wo...
Stabilizer limits and Orbit closures, applications to GCT--K V Subrahmanyam (Chennai) PHK 20.03.2024
Просмотров 179 месяцев назад
Title: Stabilizer limits and Orbit closures with applications to Geometric Complexity Theory Speaker: K V Subrahmanyam (Chennai Mathematical Institute) Abstract: Let $G\subseteq GL(X)$ be a reductive group acting on a finite dimensional vector space $V$ over $\C$. A central problem in Geometric Complexity Theory is the study points $y,z\in V$ where (i) $z$ is obtained as the leading term of the...
Virtual Legendrian knots and possible relations to causality -- V.Chernov (Dartmouth) PHK 13.03.2024
Просмотров 369 месяцев назад
Virtual Legendrian knots and possible relations to causality V.Chernov (Dartmouth) PHK 13.03.2024
Koszul-Tate resolutions and trees -- Aliaksandr Hancharuk (Jilin University, China) PHK 06.03.2024
Просмотров 439 месяцев назад
Koszul-Tate resolutions and trees Aliaksandr Hancharuk (Jilin University, China) PHK 06.03.2024
Z-graded Q-manifolds -- Alexei Kotov (Hradec-Kralove) PHK 21.02.2024
Просмотров 11210 месяцев назад
Z-graded Q-manifolds Alexei Kotov (Hradec-Kralove) PHK 21.02.2024
Conformal IDEAL covariant characterization of Kerr -- A. García-Parrado (Cordoba) PHK 13.12.23
Просмотров 35Год назад
Conformal IDEAL covariant characterization of Kerr A. García-Parrado (Cordoba) PHK 13.12.23
Unital C_∞-algebras and the real homotopy type of [some] 8-mflds -- H. Van Le (Prague) PHK 06.12.23
Просмотров 55Год назад
Unital C_∞-algebras and the real homotopy type of [some] 8-mflds H. Van Le (Prague) PHK 06.12.23
Theorem of Lusternik and Schnirelmann for reversible Finsler metrics -- S.Suhr (Bochum) PHK 29.11.23
Просмотров 131Год назад
Theorem of Lusternik and Schnirelmann for reversible Finsler metrics S.Suhr (Bochum) PHK 29.11.23
Homotopy algebras A(∞), C(∞), B(∞), hGa -- Tornike Kadeishvili (Tbilisi) PHK 22.11.2023
Просмотров 124Год назад
Homotopy algebras A(∞), C(∞), B(∞), hGa Tornike Kadeishvili (Tbilisi) PHK 22.11.2023
Internal Lagrangians of PDEs -- K. Druzhkov (Russian-Armenian University, Yerevan) PHK 15.11.23
Просмотров 41Год назад
Internal Lagrangians of PDEs K. Druzhkov (Russian-Armenian University, Yerevan) PHK 15.11.23
From the Mayer-Vietoris spectral sequence to überhomology -- Luigi Caputi (Turin) PHK 01.11.23
Просмотров 146Год назад
From the Mayer-Vietoris spectral sequence to überhomology Luigi Caputi (Turin) PHK 01.11.23
Homot. types of diff. groups of polar Morse-Bott foliations--S.Maksymenko (NAS Ukraine) PHK 11.10.23
Просмотров 40Год назад
Homot. types of diff. groups of polar Morse-Bott foliations S.Maksymenko (NAS Ukraine) PHK 11.10.23
An approach to homological algebra up to $\\epsilon$ -- Tobias Fritz (U. Innsbruck), PHK 04.10.2023
Просмотров 37Год назад
An approach to homological algebra up to $\\epsilon$ Tobias Fritz (U. Innsbruck), PHK 04.10.2023
Real cobordism theory to the Kervaire invariant one problem -- G. Li (Michigan U.), PHK 24.05.2023
Просмотров 52Год назад
Real cobordism theory to the Kervaire invariant one problem G. Li (Michigan U.), PHK 24.05.2023
Almost invariant differential calculus -- Jan Slovak (Masaryk University), PHK 17.05.2023
Просмотров 58Год назад
Almost invariant differential calculus Jan Slovak (Masaryk University), PHK 17.05.2023
On 3-nondegenerate CR manifolds in dimension 7 -- Andrea Santi (Rome "Tor Vergata"), PHK 10.05.2023
Просмотров 96Год назад
On 3-nondegenerate CR manifolds in dimension 7 Andrea Santi (Rome "Tor Vergata"), PHK 10.05.2023
Massey tensors and rational homotopy type of 7- and 8-mfds -- J. Nordström (U. Bath), PHK 03.05.2023
Просмотров 42Год назад
Massey tensors and rational homotopy type of 7- and 8-mfds J. Nordström (U. Bath), PHK 03.05.2023
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Why the 2 dislikes? :(
On second thought, the first version of condition (ii) in the definition of r-fold vector cross product was correct, after all. I checked on Lee-Leung's "Higher dimensional knot spaces for manifolds with vector cross products" and they coincided. But this could of course be a typo in their paper that I had reproduced, so there was the need for an argument for "having a nontrivial kernel does not prevent this condition to be satisfied". And this argument is actually the obvious one (on second thought): condition (ii) is not a condition on every vector in the r-fold exterior product of V but only on decomposable ones. And as such it can indeed be satisfied even in dim(\wedge^r V) > dim(V). It is actually hard to imagine this can actually be possible, and there are indeed just two exceptional situations where this happens. Thanks again, Igor, for having made me notice I had not reflected enough on this point.