Arithmetic Groups and 3-Manifolds

Arithmetic groups provide a fruitful link between various areas, such as geometry, topology, representation theory and number theory. Methods from geometry and topology hinge on the fact that arithmetic groups are lattices in Lie groups, whereas the theory of automorphic forms establishes a connection to representation theory and number theory. This interplay is especially intriguing in the setting of hyperbolic 3-manifolds. Indeed many conjectures in 3-manifold theory tend to be much more accessible for hyperbolic 3-manifolds whose fundamental groups are arithmetic, and conversely such manifolds provide the simplest set-up in which some of the most exciting new phenomena in the Langlands program can be studied. This conference will bring together researchers with various backgrounds around links between number theory and 3-manifolds. Central topics of the conference are the cohomology of arithmetic groups, the relation between torsion and L²-torsion, profinite invariants of 3-manifolds, and number theoretic ramifications.
 

Limited funding to cover travel cost and accommodation is available for early carreer participants.

The conference is planned as a hybrid event.

Who can participate?
We are currently planning to run the event according to the "3G" rule, which means you have to be fully vaccinated (with a EU-recognized vaccine, at least 2 doses, last vaccination at least 14 days previously) OR recovered from Covid (positive test min. 28 days and max. 90 days old) OR tested (certified negative test result not older than 24 h (rapid antigen test) or 48 h (PCR test)). There currently is a mask obligation in the institute.
It will be announced here, in case these regulations change.

Registration
The registration is now closed.

If you have questions, please contact a3m22@mpim-bonn.mpg.de.

For the schedule see the "details/program" above.

A conference on Algebraic Topology, in memory of Hans-Joachim Baues

This conference is intended to provide an overview of current research in homotopy theory, which has vastly expanded since its roots in the 19th century from the study of topological spaces by algebraic and combinatorial means to other fields of mathematics, including algebraic geometry, differential topology, and mathematical physics.

Live Streaming information

The talks are available in the live stream here and here

This is the fourteenth of a series of  short workshops jointly organized by the Geometry/Topology groups in Bonn, Nijmegen, and Utrecht, all situated along the Lower Rhine. The focus lies on the development and application of new structures in geometry and topology such as Lie groupoids, differentiable stacks, Lie algebroids, generalized complex geometry, topological quantum field theories, higher categories, homotopy algebraic structures, higher operads, derived categories, and related topics.

Special colloquium on the occasion of the retirement of Prof. Don Zagier as MPIM director at the end of June 2019

Conference on "Higher Homotopy Algebras in Topology", May 9 - 10, 2019

Algebras up to homotopy, or homotopy algebras, such as $A_\infty$, $C_\infty$, $E_\infty$ and $L_\infty$, play an increasingly important role in many areas of mathematics and physics, like topology, mathematical physics, and deformation theory.  Let us mention a few examples of interest. Homotopy Lie algebras, also known as $L_\infty$-algebras, have been essential in Kontsevich's proof of deformation quantization. In algebraic topology, $C_\infty$ and $L_\infty$-algebras arise as structures governing the rational homotopy type of spaces, and $E_\infty$-(co)algebras naturally appear as an algebraic structure on infinite loop spaces and on the singular (co)chains of any space. Recent advances in this line include the use of higher homotopy algebras to model all sorts of interesting spaces, such as mapping spaces, sections of fiber bundles, configuration spaces, among many others.

This mini-conference focuses on the most recent developments and applications of homotopy algebras in topology.

Organizers

Provisory list of speakers:

Arbeitstagung 2019 on Geometry, July 8 - 12, 2019

Organizers

W. Ballmann, U. Hamenstädt, and M. Kapovich

Local Organizers

W. Ballmann and C. Blohmann

Speakers 

For more information see:

https://www.hcm.uni-bonn.de/events/eventpages/hausdorff-school/hausdorff-school-2018/log-correlated-fields-2018/

Schedule June 11-14, 2018:
https://www.hcm.uni-bonn.de/events/eventpages/hausdorff-school/hausdorff-school-2018/log-correlated-fields-2018/schedule/

Conference on
Arithmetic and Automorphic Forms
on the occasion of Günter Harder's 80th birthday
March 12 - 14, 2018

Scientific Committee

Werner Ballmann, Michael Rapoport, and Joachim Schwermer

Local Organizer

Werner Ballmann and Christian Blohmann

Speakers

Kai Behrend (U British Columbia)
Spencer Bloch (U Chicago)
Gaetan Chenevier (U Paris-Sud, Orsay)
Mark Goresky (IAS Princeton)
Tasho Kaletha (U Michigan)
Stephen S. Kudla (U Toronto)
Richard Pink (ETH Zürich)
Anantharam Raghuram (IISER Pune)
Andrei Rapinchuk (U Virginia)
Peter Scholze (U Bonn)
Carlos Simpson (U Nice)
Gerard van der Geer (U Amsterdam)

Conference on "Elementare und Analytische Zahlentheorie (ELAZ)"

September 3 - 7,  2018

Organizers

Kathrin Bringmann (Universität zu Köln)
Stephan Ehlen (Universität zu Köln)
Pieter Moree (MPIM Bonn)