Paul Baum lectures 23-24th May 2016

Prof. Paul Baum, Evan Pugh Professor, Penn State will be delivering a short course on the Atiyah-Singer index theorem, aimed at a general mathematical audience. If you want to read something about the theorem in advance there is a very short article about it on the Abel Prize website:

Details below:
MONDAY 23rd May, 2-3PM, Lecture Theatre 4A, Building 54
The Dirac operator of R^n will be defined. This is a first order elliptic differential operator with constant coefficients.
Next, the class of differentiable manifolds which come equipped with an order one differential operator which at the symbol level is locally isomorphic to the Dirac operator of R^n will be considered. These are the Spin-c manifolds.
Spin-c is slightly stronger than oriented, so Spin-c can be viewed as "oriented plus epsilon". Most of the oriented manifolds that occur in practice are Spin-c. The Dirac operator of a closed Spin-c manifold is the basic example for the Hirzebruch-Riemann-Roch theorem and the Atiyah-Singer index theorem.

TUESDAY 24th May, 2-3PM, LECTURE THEATRE 4A, Building 54
This is an expository talk about the Atiyah-Singer index theorem. Some low dimensional examples of the theorem will be considered. The Dirac special case of the theorem will be proved, with the proof based on Bott periodicity. The proof will be outlined that the Dirac special case implies the full theorem.

GGSE in Oxford 27th May 2016

From Henry Wilton:

"A quick reminder about next week’s GGSE in Oxford.  First, we’re delighted to announce that Jim Howie will also talk.  The programme is as follows.

Location: Lecture Theatre 6, Andrew Wiles Building, Oxford

2pm Jim Howie (Heriot—Watt): 1-relator quotients of free products
3.15pm: Ashot Minasyan (Southampton): Conjugacy separability of non-positively curved groups
4.30pm: Henry Wilton (Cambridge): Essential surfaces in graphs

NOTE the later-than-usual start time.

As usual, further information, including times, locations and abstracts, will be available on the website: .

And finally, if you're a parent who may have difficulty attending the meeting, please don't forget about LMS childcare grants:

We’re looking forward to seeing you there!

Best wishes,


Higher Invariants at Regensburg

The DFG is funding a meeting at Regensburg from 25-29 July 2016 on the topic of Higher Invariants, interactions between arithmetic geometry and global analysis.

The meeting will include the following mini-courses

Asymptotic dimension of mapping class groups, Mladen Bestvina,

Dimension local and global, Alexander Dranishnikov

Decomposing spaces and actions, Erik Guentner

Limited funding is available for applications before May 15th.

Boundaries of CAT(0) cube complexes at Nice

Wednesday 9th-Saturday 12th March I will be attending Indira Chatterji's workshop at the Laboratoire Dieudonné de l'Université de Nice, on Boundaries of CAT(0) Cube Complexes. Mark Hagen and Michah Sageev will be delivering mini-courses on the simplicial, Roller and Poisson boundaries on Thursday and Friday.

Amenability, coarse embeddability and fixed point properties

In partnership with MSRI and the Clay institute we will be hosting a workshop entitled Amenability, coarse embeddability and fixed point properties. This will form part of the MSRI Programme "Geometric Group Theory" which runs from August 15th to December 16th 2016. Our workshop will run from 6th to 9th December. This has been organised by Goulnara Arzhantseva (University of Vienna), LEAD Cornelia Drutu (University of Oxford), Graham Niblo (University of Southampton), Piotr Nowak (Polish Academy of Sciences) and I am very grateful to the others who have done just about all the work while I have been dealing with a medical problem this summer.