******************************************************

DG, 10.40,  25.11.2016

A special seminar in honor of Prof. Oldrich Kowalski

***************************************

HA, 10.40,  27.5.2016

There is no seminar

***************************************

HA, 10.40,  20.5.2016

Lada Peksova (MFF UK), Loop homotopy algebras III.

We continue the calculations presented last time, concerning the transferred

differential on the homology. We also show the connection of the homological

perturbation lemma and physics in our formalism.

***************************************

HA, 10.40,  13.5.2016

Jan Pulmann (MFF UK), Loop homotopy algebras III.


We continue the calculations presented last time, concerning the transferred

differential on the homology. We also show the connection of the homological

 perturbation lemma and physics in our formalism.

***************************************

HA, 10.40,  6.5.2016

 Ján Pulmann (MFF UK): Loop homotopy algebras II 

Abstract.

Last time we described loop homotopy algebras as solutions of quantum master
equation. This week, we use this to build a deformation retract between 
the symmetric functions
on the original vector space of the algebra and its homology. Then, 
using the homological
perturbation lemma, we can transfer the whole master action on this 
homology,
getting a minimal model for the original algebra.

***************************************

HA, 10.40,  29.4.2016

There is no seminar. 

***************************************

HA, 10.40,  22.4.2016 

Jan Pulmann (MFF UK): Loop homotopy algebras II,


Loop homotopy Lie algebra is a generalization of homotopy Lie algebra 

which appears in Zwiebach's closed string field theory. We give its definition

and describe various alternative ways of describing its structure, notably

the description as solutions of quantum master equation.

***************************************

HA, 10.40,  15.4.2016 

  Martin Doubek (MFF UK): Homotopy tranfer for algebras over operads, III


Continuation of the previous lectures. We explain how the homotopy 

transfer results from the previous lectures by Jan Pulmann for A-infinity algebras can be 

generalized to algebras over cobar construction of an operad. This includes transfer 

for L-infinity algebras, which will be replaced by loop homotopy (a.k.a. quantum 

L-infinity) algebras in upcoming lectures.

***************************************

HA, 10.40,  8.4.2016 

  Martin Doubek (MFF UK): Homotopy tranfer for algebras over operads, II


Abstract.

Continuation of the previous lecture. We explain how the homotopy 

transfer results from the previous lectures by Jan Pulmann for 

A-infinity algebras can be generalized to algebras over cobar 

construction of an operad. This includes transfer for L-infinity 

algebras, which will be replaced by loop homotopy (a.k.a. quantum  

L-infinity) algebras in upcoming lectures.

***************************************

HA, 10.40,  1.4.2016 

Martin Doubek (MFF UK): Homotopy transfer for algebras over operads


We explain how the homotopy transfer results from the previous lectures 

by Jan Pulmann for A-infinity algebras can be generalized to algebras 

over cobar construction of an operad. This includes transfer for 

L-infinity algebras, which will be replaced by loop homotopy (a.k.a. 

 

quantum L-infinity) algebras in upcoming lectures.

***************************************

HA, 10.40,  18.3.2016 

Jan Pulmann (MFF UK): Batalin-Vilkovisky formalism and homotopy algebras, IV 

This week, we will continue developing the theory of strongly homotopy 
algebras. Building on the previous
seminar, we describe how a minimal model can be constructed using 
Feynman-like sums. This is because the minimal
model can be thought of as on-shell correlation functions of a field 
theory associated to a (cyclic) strongly homotopy algebra.

***************************************

HA, 10.40,  11.3.2016 

Jan Pulmann (MFF UK): Batalin-Vilkovisky formalism and homotopy algebras, III 


Abstract: BRSTand Batalin-Vilkovisky formalism play an important role in 

quantization of gauge theories. However, their relevance to various 

areas of mathematics has appeared recently. We will build the necessary 

background and explain their relevance to the theory of homotopy 

algebras and operads. We begin by reviewing the Batalin-Vilkovisky 

formalism and the master equation, from algebraic and geometric 

viewpoint. Then we explain how the master equation governs various 

homotopy algebras, like $L_\infty$ or $A_\infty$ algebras. These 

algebras, in turn, arise naturally when using operads. Therefore, we 

will see versions of the master equation coming from representations of 

operads,/algebras over an operad/. This week, we take a closer look at 

homotopy algebras. We review the case of Lie algebras and then 

generalize, to L_\infty A_\infty algebras. Then we can define their 

morphisms and minimal models. Finally, we will explain the connection of 

these homotopy algebras to string field theory.

***************************************

HA, 10.40,  4.3.2016 

Jan Pulmann (MFF UK): Batalin-Vilkovisky formalism and homotopy algebras, II 


Abstract: BRSTand Batalin-Vilkovisky formalism play an important role 

in quantization of gauge theories. However, their relevance to various 

areas of mathematics has appeared recently. We will build the 

necessary background and explain their relevance to the theory of 

homotopy algebras and operads. We begin by reviewing the 

Batalin-Vilkovisky formalism and the master equation, from algebraic 

and geometric viewpoint. Then we explain how the master equation 

governs various homotopy algebras, like $L_\infty$ or $A_\infty$ 

algebras. These algebras, in turn, arise naturally when using operads. 

Therefore, we will see versions of the master equation coming from 

representations of operads,/algebras over an operad/. In the second 

lecture, we will look at the geometry of BV formalism. The BV 

Laplacian in the context of graded manifolds is a divergence, so we 

will look at the generalization of Stokes theorem. This will enable us 

 

to see the gauge invariance as a consequence of the master equation.


***************************************

HA, 10.40,  26.2.2016 

  Jan Pulmann (ECI): Batalin-Vilkovisky formalism and homotopy algebras. 


Abstract: BRSTand Batalin-Vilkovisky formalism play an important role in 

quantization of gauge theories. However, their relevance to various 

areas of mathematics has appeared recently. We will build the necessary 

background and explain their relevance to the theory of homotopy 

algebras and operads. We begin by reviewing the Batalin-Vilkovisky 

formalism and the master equation, from algebraic and geometric 

viewpoint. Then we explain how the master equation governs various 

homotopy algebras, like $L_\infty$ or $A_\infty$ algebras. These 

algebras, in turn, arise naturally when using operads. Therefore, we 

will see versions of the master equation coming from representations of 

operads,/algebras over an operad/. In the first lecture, we give an 

overview and sketch the background from quantum field theory. Then we 

start with BV formalism from the algebraic viewpoint: Gerstenhaber 

brackets, BV algebras and master equation.

***************************************

HA, 10.40,  8.1.2015 

 There is no seminar (Winter school pre-meeting)

***************************************

HA, 10.40,  18.12.2015 

 There is no seminar

***************************************

HA, 10.40,  11.12.2015 

 There is seminar in Brno

***************************************

HA, 10.40,  4.12.2015 

 Leonid Positselski (ECI):  Contramodules and contraherent cosheaves in algebra and geometry 

Abstract: Contramodules are module-like algebraic structures endowed 

with infinite summation operations, understood algebraically as 

infinitary linear operations subject to natural axioms.  Simple 

counterexamples show that the contramodule infinite sum cannot be 

interpreted as any kind of limit of finite partial sums.  Thus 

contramodules represent an approach to infinite summation entirely 

different from the one commonly used in analysis.  Geometrically, 

contramodules are a kind of module structures over formal schemes and 

ind-schemes, which are an algebro-geometric version of the 

differential-geometric concept of a tubular neighborhood. 

 Globalizing contramodules to nonaffine varieties requires the concept 

of a contraherent cosheaf, which is the dual notion to that of a 

quasi-coherent sheaf. Algebraically, the definition of a contraherent 

cosheaf is based on the constructions of complete cotorsion theories in 

the categories of modules, originally developed in connection with the 

celebrated flat cover conjecture.

***************************************

HA, 10.40,  27.11.2015 

   Jan Gregorovic (ECI):  Homogeneous parabolic geometries 

Abstract: I will review the structure and construction of homogeneous parabolic 

geometries. I will show, how the existence of distinguished automorphisms influences

the structure and geometric properties of homogeneous parabolic geometries. Finally,

I will present a procedure that allows algebraically compute solutions of BGG operators

on homogeneous parabolic geometries.

***************************************

HA, 10.40,  13.11.2015 

Roger Howe (Yale University): Four stages of Classical Invariant, Stage 4 

Theory 

***************************************

HA, 10.40,  6.11.2015 

Roger Howe (Yale University): Four stages of Classical Invariant, Stage 3  

Theory 

***************************************

HA, 10.40,  30.11.2015 

Martin Doubek (MU UK, ECI): Knots, operads and graph complexes

***************************************

HA, 10.40,  23.11.2015 

 No Seminar

***************************************

HA, 10.40,  13.11.2015 

Roger Howe (Yale University): Four stages of Classical Invariant  

Theory 

***************************************

HA, 10.40,  6.11.2015 

Roger Howe (Yale University): Four stages of Classical Invariant  

Theory 

***************************************

HA, 10.40,  16.10.2015 

Roger Howe (Yale University): Four stages of Classical Invariant  

Theory 

***************************************

HA, 10.40,  2.10.2015 

Roger Howe (Yale University): Four stages of Classical Invariant  

Theory 

 

These talks will survey progress on classical invariant theory since 
Weyl’s book,
with an emphasis on more recent developments.
     They will begin with a brief review of Weyl’s results, including 
the notion of classical action,
and Weyl’s First Fundamental Theorem for such actions. This will be 
followed by the introduction
of the Weyl algebra, and the notion of dual pair of Lie subalgebras of 
the symplectic Lie algebra.
These ideas permit description of the full isotopic decomposition for 
classical actions,
not just the invariants, and also give rise to decomposition of 
polynomial rings into invariants
and harmonics relative to a given classical action. These phenomena 
suggest the concept of stable
range: when relevant parameters are restricted appropriately, various 
phenomena of interest become
more tractable. For example, in the stable range, the full polynomial 
ring can be expressed as the tensor
product of the invariants and the harmonics. This is referred to as 
separation of variables.Seeing classical
actions as part of a dual pair structure enables consideration of the 
relationship between different actions,
and leads to the study of branching rules and to reciprocity laws. These 
are formulated in terms of certain
algebras, the branching algebras. Finer investigation of these issues is 
aided by ideas from commutative
algebra, especially term orders, SAGBI theory and Hibi rings. These 
allow detailed description
of the rings of invariants and of harmonics, and provide a natural 
generalization of Hodge’s standard
monomial theory. They also enable detailed descriptions of branching 
algebras, including
a representation-theoretic approach to the Littlewood-Richardson Rule.
     Finally, the extent to which separation of variable fails outside 
the stable range will be considered.
This is the subject of current research

*********************************

*********************************

*********************************

HA, 10.40,  29.05.2015 

 U. Schreiber: Higher Cartan Geometry (Theory and applications).

A description of the contents can be found on the web address

  http://ncatlab.org/schreiber/show/Higher+Cartan+Geometry

*********************************

HA, 10.40,  22.05.2015 

 U. Schreiber: Higher Cartan Geometry (Theory and applications).

A description of the contents can be found on the web address

  http://ncatlab.org/schreiber/show/Higher+Cartan+Geometry

*********************************

HA, 10.40,  15.05.2015 

 U. Schreiber: Higher Cartan Geometry (Theory and applications).

A description of the contents can be found on the web address

  http://ncatlab.org/schreiber/show/Higher+Cartan+Geometry

*********************************

HA, 10.40,  08.05.2015 

 No seminar

*********************************

HA, 10.40,  01.05.2015 

 No seminar

*********************************

HA, 10.40,  24.04.2015 

 U. Schreiber: Higher Cartan Geometry (Theory and applications).

A description of the contents can be found on the web address

  http://ncatlab.org/schreiber/show/Higher+Cartan+Geometry

*********************************

HA, 10.40,  17.04.2015 

 U. Schreiber: Higher Cartan Geometry (Theory and applications).

A description of the contents can be found on the web address

  http://ncatlab.org/schreiber/show/Higher+Cartan+Geometry

*********************************

HA, 10.40,  10.04.2015 

 U. Schreiber: Higher Cartan Geometry (Theory and applications).

A description of the contents can be found on the web address

  http://ncatlab.org/schreiber/show/Higher+Cartan+Geometry

*********************************

HA, 10.40,  3.04.2015 

 U. Schreiber: Higher Cartan Geometry (Theory and applications).

A description of the contents can be found on the web address

  http://ncatlab.org/schreiber/show/Higher+Cartan+Geometry

*********************************

HA, 10.40,  27.03.2015 

 U. Schreiber: Higher Cartan Geometry (Theory and applications).

A description of the contents can be found on the web address

  http://ncatlab.org/schreiber/show/Higher+Cartan+Geometry

*********************************

*********************************

HA, 10.40,  20.03.2015 

 U. Schreiber: Higher Cartan Geometry (Theory and applications).

A description of the contents can be found on the web address

  http://ncatlab.org/schreiber/show/Higher+Cartan+Geometry

*********************************

*********************************

HA, 10.40,  13.03.2015 

 U. Schreiber: Higher Cartan Geometry (Theory and applications).

A description of the contents can be found on the web address

  http://ncatlab.org/schreiber/show/Higher+Cartan+Geometry

 

*********************************

 *********************************

HA, 10.40,  06.03.2015 

 U. Schreiber: Higher Cartan Geometry (Theory and applications).

A description of the contents can be found on the web address

  http://ncatlab.org/schreiber/show/Higher+Cartan+Geometry

*********************************

*********************************

HA, 10.40,  27.02.2015 

 U. Schreiber: Higher Cartan Geometry (Theory and applications).

A description of the contents can be found on the web address

  http://ncatlab.org/schreiber/show/Higher+Cartan+Geometry

*********************************

*********************************

HA, Tuesday, Feb 24, 14.00 !!! Exceptional day/time !!!

 D. Roberts (Univ. of Adelaide):  Homogeneous bundles and higher geometry

The talk will be about lifting bundles of the form G --> G/H to "String 2-bundles", i.e. to

structures involving Kac-Moody loop groups.

*********************************

HA, 10.40,  20.02.2015 

 U. Schreiber: Higher Cartan Geometry (Theory and applications).

A description of the contents can be found on the web address

  http://ncatlab.org/schreiber/show/Higher+Cartan+Geometry

*********************************

*********************************

HA, 10.40,  16.1.2015 

 ???

*********************************

HA, 10.40,  9.1.2015

 ???

*********************************

HA, 10.40,  19.12.2014 

  There is no seminar: 

*********************************************

HA, 10-11,  12.12.2014

A. Sharapov (Tomsk State University, Russia): Characteristic classes 

of Q-manifolds.

 

Abstract:  An odd vector field $Q$ on a supermanifold$M$ is called 

homological, if $Q^2=0$. The operator of Lie derivative $L_Q$ makes the algebra

of smooth tensor fields

on $M$ into a differential tensor algebra. I present a complete classification

of certain invariants of homological vector fields, called characteristic classes.

These take values in the cohomology of the operator $L_Q$ and are represented by

$Q$-invariant tensors made up of the homological vector field and

a symmetric connection on $M$ by means  of the algebraic tensor operations

and covariant differentiation. Some applications to the theory of Lie

 

algebroids and (singular) foliations will be discussed.


11-12

S. Lyakhovich**(Tomsk State University, Russia**):**BRST cohomology and quantisation of general dynamics*

Abstract:

 The talk is a review of the works on the BRST embedding and quantization of

not necessarily Lagrangian or Hamiltonian dynamics.

*********************************************

HA, 10.40,  5.12.2014

U . Schreiber (University of Nijmegen): Higher Super-WZW models

 

   I show how cocyles on super L-infinity algebras integrate to

higher WZW gerbes for sigma models on higher (categorified)

supergroups. Examples are given by the super-p-branes with tensor

multiplet fields of an extended (categorified) brane scan. This

follows arXiv:1308.5264 .

*********************************************

HA, 10.40,  28.11.2014

M. Doubek (MFF UK),  Vassiliev invariants of knots 

 

We introduce Vassiliev invariants of knots and discuss their properties, 

in particular their representability by the Kontsevich integral. We will 

try to clarify relations to the multiple zeta values and Drinfeld  associator.

*********************************************

HA, 10.40,  21.11.2014

MES seminar in Brno.

*********************************************

HA, 10.40,  14.11.2014

M. Doubek (MFF UK),  Vassiliev invariants of knots 

 

We introduce Vassiliev invariants of knots and discuss their properties, 

in particular their representability by the Kontsevich integral. We will 

try to clarify relations to the multiple zeta values and Drinfeld  associator.

*********************************************

HA, 10.40,  7.11.2014

M. Doubek (MFF UK),  Vassiliev invariants of knots 

 

We introduce Vassiliev invariants of knots and discuss their properties, 

in particular their representability by the Kontsevich integral. We will 

try to clarify relations to the multiple zeta values and Drinfeld  associator.

*********************************************

HA, 10.40,  31.10.2014

M. Doubek (MFF UK),  Vassiliev invariants of knots 

 

We introduce Vassiliev invariants of knots and discuss their properties, 

in particular their representability by the Kontsevich integral. We will 

try to clarify relations to the multiple zeta values and Drinfeld  associator.

*********************************************

HA, 10.40,  24.10.2014

 ECI seminar in Trest

********************************************

HA, 10.40,  17.10.2014

M. Doubek (MFF UK),  Vassiliev invariants of knots 

 

We introduce Vassiliev invariants of knots and discuss their properties, 

in particular their representability by the Kontsevich integral. We will 

try to clarify relations to the multiple zeta values and Drinfeld  associator.

*********************************************

HA, 10.40,  10.10.2014

M. Doubek (MFF UK),  Vassiliev invariants of knots 

 

We introduce Vassiliev invariants of knots and discuss their properties, 

in particular their representability by the Kontsevich integral. We will 

try to clarify relations to the multiple zeta values and Drinfeld  associator.

*********************************************

HA, 10.40,  3.10.2014

M. Doubek (MFF UK),  Vassiliev invariants of knots 

 

We introduce Vassiliev invariants of knots and discuss their properties, 

in particular their representability by the Kontsevich integral. We will 

try to clarify relations to the multiple zeta values and Drinfeld  associator.

*********************************************

*********************************************

*********************************************

HA, 11.00,  6.6.2014

Alex Feingold (Binghamton University ): A Lightcone Embedding of the Twin Building for a Hyperbolic  Kac-Moody Group *

 

Abstract: A twin building is a simplicial complex (with further structures) associated to a group G with a

twin BN-pair, usually constructed from the parabolic subgroups of G. A hyperbolic Kac-Moody group G

over the complex numbers is associated with a hyperbolic Kac-Moody Lie  algebra g = g(A), where A is

a hyperbolic type Cartan matrix that determines g by generators and relations. The invariant symmetric

bilinear form ( , ) on the standard Cartan subalgebra h in g has signature (n-1,1) on the split real form

of h, providing a Lorentzian geometry. The usual root system data of g gives a twin BN-pair for G, and thus a

twin building. The Cartan-Chevalley involution on g gives a ``compact" real form k of g, a real Lie algebra

whose complexification is g, whose Cartan subalgebra t also has Lorentzian form ( , ), and there is also

a corresponding compact real group K. We are able to embed the twin building for G inside

the union of all ``lightcones" {x in k | (x,x) <= 0} which is in the union of all K conjugates of t.

     This provides a geometrical realization of the twin building of G closely related to the structure of all

Cartan subalgebras in k, and sheds light on the geometry of the infinite dimensional groups G and K. This is

especially interesting in the case of rank 3 hyperbolic algebras whose Weyl groups are hyperbolic triangle

groups, so that the building is a union of copies of the tesselated Poincar? disk with certain boundary lines

identified. This is joint work with Lisa Carbone (Rutgers University and Walter Freyn (TU-Darmstadt).

**********************************************

HA, 11.00,  23.5.2014

 I. Kriz (Ann Arbor): D-structures and derived Koszul duality for unital operad algebras

 

 Abstract: I will discuss how to make sense of derived Koszul duality

 for operad algebras with unit. I will also explain how this relates to,

 and, in a sense, generalizes, derived Koszul duality for PROPs,

 and how the unital case relates to ideas about Koszul duality

 with curvature (including the results of a recent paper of Hirsch and

 Milles).  Our results were inspired by D-structures, which were introduced

 in bordered Floer homology by Lipshitz, Oszvath and Thurston.

 This talk is about joint work with Tyler Foster and Po Hu.

**********************************************

HA, 10.40,  16.5.2014

B. Jurco: On Chern-Simons action and the Jones polynomials

**********************************************

HA, 10.40,  8.5.2014

No seminar

**********************************************

HA, 10.40,  1.5.2014

No seminar

**********************************************

HA, 10.40,  25.4.2014

L. Krizka: KZ equation, monodromy and conformal blocks 

**********************************************

HA, 10.40,  18.4.2014

No seminar

**********************************************

HA, 10.40,  11.4.2014

L. Krizka: KZ equation, monodromy and conformal blocks 

**********************************************

HA, 10.40,  4.4.2014

L. Krizka: KZ equation, monodromy and conformal blocks 

**********************************************

HA, 10.40,  28.3.2014

L. Krizka: KZ equation, monodromy and conformal blocks 

**********************************************

HA, 10.40,  21.3.2014

L. Krizka: KZ equation, monodromy and conformal blocks 

**********************************************

HA, 10.40,  14.3.2014

L. Krizka: KZ equation, monodromy and conformal blocks 

**********************************************

HA, 10.40,  7.3.2014

D. Mylonas (Heriot-Watt University, Edinburgh) : 

Nonassociative deformations of non-geometric fluxed backgrounds in closed string theory

 

Abstract:

Non-geometric fluxed backgrounds arise as consistent vacua of string 

theory via T-duality transformations of conventional backgrounds endowed 

with p-form fluxes. In this talk we will discuss how such backgrounds 

are geometrised by the dynamics of an open membrane sigma-model embedded 

in the standard Courant algebroid. The boundary of this theory is a 

quasi-Poisson sigma-model in phase space twisted by an abelian gerbe in 

momentum space, whose correlation functions reproduce Kontsevich's 

formalism of global deformation quantization. For the case of constant 

flux, we will find a closed formula for the corresponding nonassociative 

star product and its associator. This quantization will then be related 

to cochain twist quantization via suitable quasi-Hopf algebras of 

symmetries of R-fluxed phase space. In this context we will compute the 

pertinent deformed differential calculus and discuss possible 

realisations of nonassociative deformations of gravity. 

**********************************************

HA, 10.40,  27.2.2014

M. Doubek: Invariants of knots 

**********************************************

HA, 10.40,  21.2.2014

 M. Doubek: Invariants of knots

**********************************************

**********************************************

**********************************************

HA, 10.40,  10.1.2014

 Winter school in Srni, 2014, preparation

**********************************************

HA, 10.40,  3.1.2014

The seminar is cancelled

**********************************************

**********************************************

HA, 10.40,  13.12.2013

B. Jurco: Invariants of knots - Yang-Baxter equation in statistical physics

**********************************************

HA, 10.40,  6.12.2013

L. Krizka: Drinfeld categories

**********************************************

HA, 10.40,  29.11.2013

R. O'Buachalla: Invariants of knots

**********************************************

HA, 10.40,  22.11.2013

R. O'Buachalla: Invariants of knots

**********************************************

HA, 10.40,  15.11.2013

R. O'Buachalla: Invariants of knots

**********************************************

HA, 10.40,  8.11.2013

R. O'Buachalla: Invariants of knots

**********************************************

HA, 10.40,  1.11.2013

M. Doubek: Invariants of knots

**********************************************

HA, 10.40,  25.10.2013

M. Doubek: Invariants of knots

**********************************************

HA, 10.40,  18.10.2013

M. Doubek: Invariants of knots

**********************************************

HA, 10.40,  4.10.2013

U. Pennig: Unit spectra of K-theory via strongly self-absorbing C*-algebras


Abstract. I will speak about an operator algebraic model for the first space of 

the unit spectrum of complex topological K-theory, i.e. BGL_1(KU), and related

infinite loop spaces via bundles of stabilized strongly self-absorbing C*-algebras.

The proof that the classifying space of these bundles has the right homotopy type

is based on the I-monoid model for GL_1(KU)  developed by Sagave and Schlichtkrull.

  I will try to keep the material self-contained, so no prior knowledge of C*-algebras is

required to follow the talk. The results are joint work with Marius Dadarlat from Purdue.

**********************************************

**********************************************

HA, 10.40,  24.5.2013

No seminar - MES in Brno

**********************************************

HA, 10.40,  17.5.2013

 No seminar

**********************************************

HA, 10.40,  10.5.2013

I. Kriz (University of Michigan): Elliptic cohomology

Abstract: I will briefly introduce the idea of elliptic
cohomology, how it is constructed and why
the topic is still alive mathematically. The last part concerns
conjectured connections with analysis and geometry
which have not been established so far, even though several
attempts have been made.

***********************************************

HA, 10.40,  3.5.2013

M. Fischmann: Conformal powers of the Dirac operator via tractors

***********************************************

HA, 10.40,  26.4.2013

M. Fischmann: Conformal powers of the Dirac operator via tractors

***********************************************

HA, 10.40,  19.4.2013

V. Soucek - Howe duality for orthosymplectic Lie superalgebras

***********************************************

HA, 10.40,  12.4.2013

D. Eelbode (Ghent University):  Fueter theorem from representation point of view

***********************************************

HA, 10.40,  5.4.2013

D. Smid - Fisher decomposition for orthosymplectic Lie superalgebras

************************************************

HA, 10.40,  29.3.2013

No seminar (Eastern)

***********************************************

HA, 10.40,  22.3.2013

D. Smid - Fisher decomposition for orthosymplectic Lie superalgebras

***********************************************

HA, 10.40,  15.3.2013

D. Smid - Fisher decomposition for orthosymplectic Lie superalgebras

***********************************************

HA, 10.30,  8.3.2013

Central European seminar in Brno

***********************************************

HA, 10.30,  1.3.2013

Pavel Chalmoviansky -
"What is to be expected around a singular point of plane algebraic curve?"

Anotace:
We give an  overview of several results  concerning singularities, their
visualizations  and  their  application  in modeling.   We  consider  an
isolated  singular  point  of  complex plane  algebraic  curve  and  its
invariants  such  as  Milnor  number  and the  associated  knot  of  the
singularity. Such a singularity can  be resolved via sequence of blowups
or by a  suitable unfolding. We give examples and  visualizations of the
whole  process.  For  a special  class  of curves,  we characterize  the
singular points  at infinity.  In  real spaces,  we consider a  study of
relative position of a cone and  a parabolic Bezier segment motivated by
Minkowski space. Singularities are used to determine boundary cases.

***********************************************

HA, 10.30,  22.2.2013

David M.J. Calderbank (Bath) - Kostant's theorem: a geometrical perspective.

 

The spectral decomposition of Kostant's laplacian may be viewed

as a computation on a homogeneous (or flat) Cartan geometry. From

this perspective, Kostant's result may be obtained using a first

order Weitzenbock formula relating the first order laplacian with

the curved Casimir operator on tractor-valued forms. The Weitzenbock

formula also applies in the curved case, adding an interesting

ingredient to the BGG calculus.

***********************************************

HA, 10.30,  11.1.2013

J. Nekovar (Paris) - Branching rules and diophantine equations

Abstract:

Modularity of elliptic curves implies that every elliptic curve E defined
over Q is parameterised, in many different ways, by modular and
Shimura curves. These curves are equipped with coherent families
of points defined over suitable (generalised) dihedral extensions of Q.
Non-triviality of the images of these points on E is governed by suitable
branching rules for groups SO(W) \subset SO(V) (dim W = 2, dim V = 3) over
local fields and adeles.

***********************************************

HA, 10.30,  4.1.2013

Seminar related to organization of WS, Srni

***********************************************

HA, 10.30,  21.12.2012

There is no seminar

***********************************************

HA, 10.30, 14.12.2012

T. Kobayashi (Univ. of Tokyo): Finite multiplicity theorems and real
spherical varieties

Abstract:
      We introduced the concept of "Real Spherical Varieties" that
assure finite multiplicity property of irreducible infinite dimensional
representations on function spaces. More generally, I plan to discuss
geometric conditions that control the multiplicities of irreducible
representations of real reductive groups occurring in branching laws
(restriction) and Plancherel formulas (induction).

***********************************************

HA, 10.30, 7.12.2012

 U. Pennig (University of Munster): Twisted K-theory

 Abstract:

Twisted K-theory was first studied by Donovan and Karoubi, who called
it K-theory with local coefficients. The twists considered by them and
also later by Atiyah and Segal are represented by classes in the third
cohomology group of the underlying space. From the point of view of
stable homotopy theory, the classifying space of the units in the
K-theory spectrum $BGL_1(KU)$, which classifies all twists, is much
bigger than that: Its homotopy type is $BZ/2Z \times BBU_{\otimes}$.
We give an operator algebraic description of these higher twists,
which parallels the construction of the ordinary twists via bundles of
compact operators.

***********************************************

HA, 10.30, 30.11.2012

 CES in Brno

***********************************************

HA, 10.30, 23.11.2012

 B. Jurco:   Introduction to string theory, I.

***********************************************

HA, 10.30, 16.11.2012

 B. Jurco:   Introduction to string theory, I.

***********************************************

HA, 10.30, 9.11.2012

 B. Jurco:   Introduction to string theory, I.

***********************************************

HA, 10.30, 2.11.2012

 B. Jurco:   Introduction to string theory, I.

This will be the first seminar of the series devoted to certain chapters
of the book by B. Zwiebach:

http://stringworld.ru/files/Zwiebach_B._A_first_course_in_string_theory_...

***********************************************

HA, 10.30, 26.10.2012

B. Jurco: Introductory seminar in string theory

*********************************

HA, 10.30, 12.10.2012

Leticia Barchini (Oklahoma State University): Geometric models for a class of
unitary representations, Lecture 2

This will be a series of three lectures on the following topic.

Lecture 2 

Given an admissible irreducible (g, K)-module, a theorem of
Harish-Chandra guarantees that such module is the Harish-Chandra module
(i.e the space of K-finite vectors) of an irreducible representation of G.
Such equivalent class of G-representation is not unique. The different
equivalent classes of G-representations with equivalent Harish-Chandra
modules are called the globalizations of the (g,K)-module. There is always
a maximal and a min- imal globalization. These globalizations are
topological dual of each other. In the case of Aq(?), the maximal
globalization occurs in spaces of Dolbeault cohomology and the minimal
globalization occurs as compactly supported cohomology. 

The problem of
describing the unitary gobalization of cohomologically induced modules is
open. I will survey the state of the problem, describe some of the methods
that have been used and or proposed indicating their partial successes. I
will focus on the various geometric-analytic subtletie of the problem. This
lecture will focus on the method known as "Indefinite quantization" and its
variants.   

*********************************

HA, 10.30, 5.10.2012

Leticia Barchini (Oklahoma State University): Geometric models for a class of
unitary representations, Lecture 1

This will be a series of
three lectures on the following topic.

An open problem in representation
theory is to find explicit geometric models for irreducible unitary
representations of a real reductive group G. The space of equivalent
classes of unitary irreducible representations of G is in bijection with
the space of unitarizable irreducible Harish-Chandra mod- ules. In these
series of talk I will focus of those representations "attached" to elliptic
co-adjoint orbits. Their Harish-Chandra modules are the cohomolog- ically
induced modules, Aq(?). The aim is to build the unitary globalization of
Aq(?) that are, by algebraic methods, known to be unitarizable. In most
cases, the Hilbert space that exhibits the module as unitary is not known.

Lecture 1 

In the first lecture I will discuss aspects of the
philosophy of the orbit method, illustrating the method when G = SL(2, R).
Next, I will review the classification of elliptic orbits and briefly
describe the algebraic construction of cohomologically induced modules.

*********************************

HA, 10.30, 20.4.2012

Z. Sir: Diskretni diferencialni geometrie, IV. cast

*********************************

HA, 10.30, 13.4.2012

Z. Sir: Diskretni diferencialni geometrie, III. cast

*********************************

HA, 10.30, 6.4.2012

There is no seminar

*********************************

HA, 10.30, 30.3.2012

Z. Sir: Diskretni diferencialni geometrie, II. cast

**********************************

HA, 10.30, 23.3.2012

Z. Sir: Diskretni diferencialni geometrie, I. cast

*********************************

HA, 10.30, 9.3.2012

MES Brno

*********************************

HA, 10.30, 2.3.2012

V. Tucek - Unitary representation with highest weights 
and their cohomologies II.

*********************************

HA, 10.30, 24.2.2012

V. Tucek - Unitary representation with highest weights 
and their cohomologies I.

*********************************

*********************************

HA, 10.30, 13.1.2012

There is no seminar

*********************************

HA, 10.30, 6.1.2012

WS Srni seminar

*********************************

HA, 10.30, 16.12.2011

The seminar is cancelled

*********************************

HA, 10.30, 9.12.2011

Vladimir Ezhov - Perturbed determinants and longest cycles on a graph.

*********************************

HA, 10.30, 2.12.2011

MES in Brno

*********************************

HA, 10.30, 25.11.2011

Z. Sir - Finite type geometry

*********************************

HA, 10.30, 18.11.2011

Seminar zrusen

*********************************

HA, 10.30, 11.11.2011

A. Juhl - On the structure of GJMS-operators

GJMS-operators are conformally invariant powers of the Laplacian. Their structure is very complicated and mysterious. In the lectureI will describe the origin of systems of identities involving these operators and how these lead to insight into their structure.

*********************************

HA, 10.30, 4.11.2011

T. Milev - Branching, vector partition function and all that

*********************************

HA, 10.30, 28.10.2011

October's fiest (no seminar)

*********************************

HA, 10.30, 21.10.2011

MES Telc 

*********************************

HA, 10.30, 14.10.2011

P. Pandzic: Translation principle for Dirac index

Let G be a connected real reductive Lie group with maximal compact subgroup
K of equal rank and with complexified Lie algebra g. If X is a (g,K)-module,
then the Dirac cohomology of X splits into even and odd parts, and Dirac
index is defined as their formal difference. We study how Dirac index can
vary in a coherent family of (virtual) (g,K)-modules. This is joint work in
progress with Salah Mehdi and David Vogan.

*********************************

HA, 10.30, 7.10.2011

L. Schwachhoefer - Euclidean and hyperbolic monopoles.

********************************* 

*********************************

HA, 10.30, 3.6.2011

T. Salac - BGG category O

*********************************

HA, 10.30, 20.5.2011

T. Salac - BGG category O

*********************************

HA, 10.30, 13.5.2011

ECC Radejov

*********************************

HA, 10.30, 6.5.2011

D. M. J. Calderbank: Parabolic subgeometries - un update.

*******************************

HA, 10.30, 29.4.2011

D. M. J. Calderbank: H-projective structures - a lost parabolic geometry?

*********************************

HA, 10.30, 22.4.2011

H. De Bie - Clifford-Fourier transform and Hermite semigroups

*********************************

HA, 10.30, 15.4.2011

B. Jurco - Hamiltonian reduction + Calogero-Moser systems

*********************************

HA, 10.30, 8.4.2011

T. Salac - BGG category O

*********************************

HA, 10.30, 1.4.2011

Special seminars

*********************************

HA, 10.30, 25.3.2011

T. Salac - BGG category O

*********************************

HA, 10.30, 18.3.2011

Z. Vlasakova - Symetrie CR Laplaceova operatoru

*********************************

HA, 10.30, 11.3.2011

Z. Vlasakova - Symetrie CR Laplaceova operatoru

*********************************

HA, 10.30, 4.3.2011

MES in Brno

*********************************

HA, 10.30, 25.2.2011

T. Salac - Elliptic complexes in Clifford Analysis

*********************************

HA, 10.30, 14.1.2011

No seminar

*********************************

HA, 10.30, 7.1.2011

No seminar

*********************************

HA, 10.30, 17.12.2010

V. Soucek - Cherednik algebras and their representation theory

*********************************

HA, 10.30, 10.12.2010

V. Soucek - Cherednik algebras and their representation theory

*********************************

HA, 10.30, 3.12.2010

The seminar is cancelled

*********************************

HA, 10.30, 26.11.2010

P. Somberg - Representation theory and D-modules

*********************************

HA, 10.30, 19.11.2010

(Lecture given in Mikulov)

Lorenz Schwachhoefer - Extrinsic symmetric spaces

*********************************

 

*********************************

DG, 10.30, 15.10.2010

P. Somberg - Representation theory and D-modules

 *********************************

DG, 10.30, 8.10.2010

P. Somberg - Representation theory and D-modules

*********************************

DG, 10.30, 1.10.2010

P. Somberg - Representation theory and D-modules

*********************************

DG, 10.30, 1.10.2010

Seminar se nekona

*********************************

*********************************

*********************************

DG, 10.30, 28.5.2010

MES in Brno

*********************************

DG, 10.30, 21.5.2010

Z. Sir - Problemy geometrickeho modelovani 

*********************************

DG, 10.30, 14.5.2010

Z. Kasarova - Introduction to CR geometry 

*********************************

DG, 10.30, 7.5.2010

W. Sabadani: Slice hyperholomorphic functions and the Fueter mapping 
theorem in integral form
 

F. Colombo: Fhe functional calculi associated to slice hyperholomorphic 
functions.

*********************************

DG, 10.30, 30.4.2010

MES, Brno    

*********************************

DG, 10.30, 23.4.2010

Z. Kasarova - Introduction to CR geometry 

*********************************

DG, 10.30, 16.4.2010

S. Krysl - Symplekticke spinory   

*********************************

DG, 10.30, 9.4.2010

P. Pandzic (Zahreb University) - Dirac cohomology and generalized Bott-Borel-Weil Theorem

**********************************

DG, 10.30, 2.4.2010

The seminar is cancelled

*********************************

DG, 10.30, 26.3.2010

S. Krysl - Symplekticke spinory  

**********************************

DG, 10.30, 19.3.2010

S. Krysl - Symplekticke spinory

**********************************

DG, 10.30, 12.3.2010

L. Krizka - Geometric methods in representation theory  

**********************************

DG, 10.30, 5.3.2010

L. Krizka - Geometric methods in representation theory  

*********************************

DG, 10.30, 26.2.2010

MES, Brno

**********************************

HA, 10.30, 15.1.2010

The seminar is cancelled 

**********************************

HA, 10.30, 8.1.2010

Winter school Srni (preparation); the meeting is at 10! 

**********************************

HA, 10.30, 18.12.2009

Branislav Jurco - Introduction to nonabelian bundle gerbes

**********************************

HA, 10.30, 11.12.2009

MES in Brno

**********************************

HA, 10.30, 4.12.2009

S. Krysl - Svazky a jejich kohomologie

**********************************

HA, 10.30, 27.11.2009

S. Krysl - Svazky a jejich kohomologie

**********************************

HA, 10.30, 20.11.2009

S. Krysl - Svazky a jejich kohomologie

**********************************

HA, 10.30, 13.11.2009

S. Krysl - Svazky a jejich kohomologie

**********************************

HA, 10.30, 6.11.2009

T. Salac - Dirac operators in many variables

**********************************

HA, 10.30, 30.10.2009

Seminar is cancelled

**********************************

HA, 10.30, 23.10.2009

T. Salac - Dirac operators in many variables

**********************************

HA, 10.30, 16.10.2009

Thang Le - Hyperbolic volume, torsion growth, and L2-torsion

**********************************

HA, 10.30, 9.10.2009

V. Tucek - Symetrie Laplaceova operatoru

**********************************

HA, 10.30, 2.10.2009

MES in Brno

**********************************

**********************************

**********************************

HA, 10.30, 22.5.2009

P. Franek -

**********************************

HA, 10.30, 15.5.2009

T. Salac - Explicit form of generalized Dolbeault complexes

**********************************

HA, 10.30, 17.4.2009

MES in Brno

**********************************

HA, 10.30, 10.4.2009

The seminar is cancelled

**********************************

HA, 10.30, 3.4.2009

P. Franek - Cartan for beginners

**********************************

HA, 10.30, 27.3.2009

P. Franek - Cartan for beginners

**********************************

HA, 10.30, 20.3.2009

P. Franek - Cartan for beginners

**********************************

HA, 10.30, 13.3.2009

P. Franek - Cartan for beginners

**********************************

HA, 10.30, 6.3.2009

Ren - ???

**********************************

HA, 10.30, 27.2.2009

MES, Brno

**********************************

**********************************

HA, 10.30, 16.1.2009

L. Krizka, P. Somberg - Stability in abelian categories and D-branes 

**********************************

HA, 10.30, 9.1.2009

 

 

**********************************

DG, 9.00, 19.12.2008

CES, Brno  

**********************************

DG, 9.00, 12.12.2008

Workshop on Clifford Analysis

**********************************

HA, 10.30, 5.12.2008

P. Franek - Cartan for beginners 

**********************************

HA, 10.30, 28.11.2008

P. Franek - Cartan for beginners 

**********************************

HA, 10.30, 21.11.2008

P. Franek - Cartan for beginners

**********************************

HA, 10.30, 14.11.2008

ECC seminars Friday+Saturday (Telc/Trest)

**********************************

HA, 10.30, 7.11.2008

P. Franek - Cartan for beginners

**********************************

HA, 10.30, 31.10.2008

L. Krizka, M. Sikora - Alg. Geometry, D-modules and Fourier-Mukai transform 

**********************************

HA, 10.30, 24.10.2008

L. Krizka, M. Sikora - Alg. Geometry, D-modules and Fourier-Mukai transform 

**********************************

HA, 10.30, 17.10.2008

V. Tucek, T. Salac - Geometry of algebraic stacks 

**********************************

HA, 10.10.2008

CES, Brno

**********************************

HA, 10.30, 3.10.2008

V. Tucek, T. Salac - Geometry of algebraic stacks 

**********************************

**********************************

HA, 10.30, 23.5.2008

V. Soucek - Holonomic D-modules and their applications 

**********************************

HA, 10.30, 16.5.2008

V. Soucek - Holonomic D-modules and their applications

**********************************

HA, 10.30, 9.5.2008

The seminar is cancelled due to the feast

**********************************

HA, 10.30, 2.5.2008

K. Pazourek - Cayleho rovina

**********************************

HA, 10.30, 25.4.2008

S. Chiossi -

**********************************

HA, 10.30, 18.4.2008

Seminar MES in Brno

**********************************

HA, 10.30, 11.4.2008

P. Somberg - Introduction to D-modules

**********************************

HA, 10.30, 4.4.2008

No seminar

**********************************

HA, 10.30, 28.3.2008

P. Somberg - Introduction to D-modules

**********************************

HA, 10.30, 21.3.2008

Easter feast

**********************************

HA, 10.30, 14.3.2008

Seminar MES in Brno

**********************************

HA, 10.30, 7.3.2008

P. Somberg - Introduction to D-modules

**********************************

HA, 10.30, 29.2.2008

P. Somberg - Introduction to D-modules

**********************************

HA, 10.30, 22.2.2008

P. Somberg - Introduction to D-modules

**********************************

 

WS, Srni

 

**************************************

HA, 10.30, 2.10.2009

MES in Brno

 

HA, 10.30, 23.10.2009

?

**************************************

HA, 10.30, 16.10.2009

?

Undefined