Floer Lectures 2018
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Triangle Trim


  JUNE 21-22, BOCHUM


We are delighted to have Victor Guillemin (MIT) and Paul Seidel (MIT) as our two speakers. They will each give two talks.

This is a workshop hosted by the Floer Center of Geometry and funded by the Bochum-Cologne SFB collaboration program CRC/TRR 191 "Symplectic Structures in Geometry, Algebra and Dynamics”.           




15:15-16:15 V. Guillemin - "Superposition of Coherent states"

16:15-17:00 Coffee break

17:00-18:00 V. Guillemin - "On geometric quantization of b-symplectic manifolds"



15:15-16:15 P. Seidel - "Lefschetz pencils and their noncommutative counterparts I" 

16:15-17:00 Coffee break

17:00-18:00 P. Seidel - "Lefschetz pencils and their noncommutative counterparts II"


Talks will take place in room NA 01/99, which is on the ground floor of the Mathematics Department (building NA).

Coffee breaks will take place in the Friedrich-Sommer Raum NA 1/58, which is on the first floor up of the same building.



P. Seidel - "Lefschetz pencils and their noncommutative counterparts" 

Lefschetz' approach to understanding the topology of an algebraic variety was to consider its intersections
with a moving family of parallel hyperplanes. Such a family of intersections is called a "pencil", and those
with the mildest possible singularities are called "Lefschetz pencils". (The name may be puzzling now, but
pencil has an obsolete meaning as "paintbrush", in parallel with French "pinceau", and each intersection is thought of as a hair of that brush).


V. Guillemin - "Superposition of Coherent states" 

We will show in this talk how one can construct solutions of semi-classical partial differential equations such as, for instance, the Schroedinger equation by expressing the initial data as superpositions of coherent states and then solving these equations with these coherent states as initial data.  (The virtue of doing this is that these coherent state solutions have nice geometric properties. For instance, for the Schroedinger operator associated with a Riemann metric on curved space-time their singularities are concentrated on single closed geodesics of the metric.)


V. Guillemin - "On geometric quantization of b-symplectic manifolds"

In the first part of this lecture  we will review what's known  about actions of tori on Poisson manifolds and discuss some of the problems one encounters in attempting to quantize such actions. Then in the second part we will show how this can be done in one important case by converting the Poisson bi-vector field into a symplectic form that blows up along a b-hypersurface.


Anyone is welcome to attend!

There is no formal registration, but please send an email to Frau Dittmann (annika.dittmann@rub.de) so that we can estimate the number of participants. Everyone is welcome to join us for a dinner on the Thursday evening.



Here are some of the hotels in Bochum, please contact Frau Dittmann if you would like assistance with booking a room.

Park Inn - conveniently located next to central station, large rooms, but not cheap (ca 85 Euro incl. breakfast)).

Ibis City und Ibis Zentrum - next to central station, small rooms, good price but nothing special - Ibis Zentrum is probably a bit more quiet (ca 65 incl. breakfast).

Art Hotel Tucholsky in the "Bermuda triangle" (party mile), that is, can be noisy at night, but if you reserve a room to the back yard it's very fine, art hotel with funny accessoires - great breakfast, probably the most interesting hotel in the list (ca. 75 Euros incl. breakfast)

Jugendherberge (youth hostel) Bochum again in the "Bermuda triangle", it is supposed to be very good and has differnet kinds of rooms (ca. 62 Euros for single rooms incl. breakfast)

General directions including a map of the campus can be found here.

For assistance or questions please contact Annika Dittmann.


 We hope to see you there!