# Events

# Events 2006

**The 2006 Twente conference on Lie groups
**

*December 13th, 2006*

From 13-15 December 2006 the annual Twente conference on Lie groups takes place. For more information contact Gerard Helminck by sending an email to helminckgf@cs.utwente.nl

**J. Martens (MPI) in Utrecht
**

*November 30th, 2006*

J. Martens will speak in the geometry and topology seminar.

**Title**: Equivariant volumes of non-compact quotients and instanton counting

**Location and time**: 14:00-15:00 in room 611a in the math building

**Mini-workshop on index theory of singular spaces
**

*November 28th and 29th, 2006*

**Location**: RU Nijmegen, Huygens Building (FNWI)

**Schedule 28th
**10:45- 12:00

**Walter van Suijlekom**(MPIM),

*Local index formula for SU_q(2)*

13:45-14:30 & 14:45-15:30

**Varghese Mathai**(Adelaide)

*Twisted index theory on orbifolds I+II*

16:00-17:15

**Hessel Posthuma**(Utrecht)

*Cyclic homology theory of deformations over orbifolds*

Location: HG01.057

**Schedule 29th
**10:15 – 11:30

**Markus Pflaum**(Mainz)

*Algebraic index theory and deformations over orbifolds*

12:45-13:30 & 13:45-15:00

**Varghese Mathai**(Adelaide)

*Twisted index theory on orbifolds III+IV*

**Note!** All talks are meant for an audience with good knowledge of index theory, K-theory and noncommutative geometry

**GQT-Colloquium
**

*November 24th, 2006*

Joint meeting of the GQT-Colloquium and the Utrecht joint seminar on mathematical physics

**Schedule**

14:00-15:00 **Varghese Mathai** (Adelaide), *T-duality in a background H-flux
*15:15-16:15

**Erik Verlinde**(UvA),

*Strings, Symmetric Products and the Elliptic Genus*

16:20-???? reception

**Location**: UU Mathematics Building, room K11

**Colloquium Lecture by Varghese Mathai
**

*November 23rd, 2006*

15.30-16.30, Utrecht Colloquium lecture

**Varghese Mathai** (Adelaide): *On a curious extension of the Atiyah-Singer index theorem*

**Location**: room K11, Mathematics Building

**Mathai Varghese at UvA
**

*November 20th, 2006*

Mathai Varghese (Adelaide, Australia) will give a talk at the KdVI institute on his recent work with Melrose and Singer on index theory (math.DG/0402329 + followup work).

Title: Fractional Analytic Index.

Time: Monday November 20, from 11-12,

Room: P0.19 (gebouw Euclides, Plantage Muidergracht 24),

**Colloquium lecture by J.D. Lewis
**

*November 16th, 2006*

15.30-16.30, Utrecht Colloquium Lecture

**J.D. Lewis** (Alberta): *Variants of the cycle class map
*Location: room K11, Mathematics Building

**UU Topology & Geometry lecture by E. Emsiz (UvA)
**

*November 9th, 2006*

14.00-15.00 Room 611a mathematics building

**Title:** Affine Weyl groups and integrable systems with delta potentials

**IMAPP Symposium “The Origin of the Universe: Mathematics, Astrophysics or Particle Physics?”
**

*October 13th, 2006*

**Scientific Meeting at the Cluster Opening
**

*October 10th, 2006*

Time: 13:00-16:00

Location: Belle van Zuylenzaal, Academiegebouw Utrecht

**Speakers**

13:30-14:30 **Pierre Cartier** (IHES, France) *Towards a “cosmic Galois group”: two parallel hierarchies of polyhedra and their meaning for number theory and quantum field theories
15:00-16:00 Alan Weinstein (UC Berkeley, USA) The quantum torus as a quantum “group”*

Registration via NWO-website is required!

**Official opening ceremony of the GQT-cluster by Minister of Education
**

*October 10th, 2006*

Time: 16.00-17.30, followed by drinks at 17:30

Location: Senaatszaal, Academiegebouw Utrecht

Meeting of the Mathematical Clusters at the occasion of the official opening of the GQT-cluster by the Minister of Education, Culture and Science.

Registration via NWO-website is required!

**Modular forms, October 8-13
**

*October 8th, 2006*

The topic of the conference is the theory of modular forms, both the geometric as well as the arithmetic aspects.

Expected participants include: Bergstr�m, Boecherer, Bosman, Bruinier, Diamond, Edixhoven, Faber, van der Geer, Gritsenko, Grushevski, Ibukiyama, R. de Jong, Katsura, Kondo, Kudla, Meagher, Moonen, Pollack, Rajan, Rastegar, Salvati-Manni, Savin, Shepherd-Barron, Taelman, Wiese, Zagier.

The conference is held at the traditional Hotel van der Werff on Schiermonnikoog island, the Netherlands.

**Symposium “Geometry in Autumn” (September, 28th-29th)
**

*September 28th, 2006*

This short symposium at the Lorentz Centre in Leiden is devoted to recent developments in complex algebraic geometry. Some of the topics the symposium focuses on are moduli spaces, algebraic curves and surfaces, and vector bundles. We will also look back and evaluate the developments since the symposium ‘Geometry in Autumn I’ held about ten years ago on the occasion of the retirement of Van de Ven.

Speakers: E. Amerik, W. Barth, A. Beauville, F. Catanese, G. Deschamps, G. Farkas, K. Hulek.

Lectures will start on Thursday September 28 at 2 pm. The symposium will end in the early afternoon of Friday.

Participants are requested to register at the Lorentz Center.

Organizers: Bas Edixhoven, Gerard van der Geer Martin Luebke

**Lectures by Jan Stienstra and Vasily Golyshev
**

*September 22nd, 2006*

Intercity Number Theory Seminar

**Schedule**

13:00-14:00 **Vasily Golyshev** (Moscow), *Spectra and Their Arithmetic
*14:15-15:15

**Jan Stienstra**(Utrecht),

*Apery-like numbers, differential equations of type DN and dimer models*

**Location**: UU Mathematics Building, room K11

**Lecture by Alessio Corti
**

*September 20th, 2006*

Time: 16.15-17.15

**Alessio Corti** (Imperial College): *Orbifold quantum cohomology of Fano toric stacks
*Location: room K11, Mathematics Building