COMBINATORICS, TOPOLOGY AND CONVEXITY:
THEIR MEETING POINTS

27 April -5 May 2003

Organizer: GIL KALAI

Hebrew University's Institute for Advanced Studies - Feldman Building, Givat Ram, Safra campus.
Unless specified otherwise lectures will take place on Lecture Hall 130 Feldman building. The Erdos' lecture On Thursday May 1 at 16:00 and later lectures on Thursday and on Friday May 2 will take place in the Mathematics building lecture hall 2.

PROGRAM

27 April
8:30-9:30 Registration in the Lobby of the Institute.

Lecture Hall 130: Feldman building

9:45 Welcome
10:00-11:10 Francesco Brenti - Combinatorics of Schubert varieties I

Coffee Break

11:30-12:40 Eric Babson - f-vectors I
14:30-15:40 Yoav Segev - Finite groups acting on acyclic complexes I
16:00-16:55 Yael Karshon - Euler-Maclaurin formula for polytopes

Coffee Break

17:10-18:05 Peter Csorba - Topological lower bound for Chromatic numbers

18:30 - Reception in the Lobby of the Institute.

28 April

Lecture Hall 130: Feldman building

9:15-10:25 Alexander Barvinok - Wild convex bodies I

Coffee Break

10:45-11:55 Sergey Fomin - Generalized associahedra and cluster algebras I
12:00-12:55 Micha A. Perles- Non-Convexity
14:30-15:25 Nati Linial - Lifts of graphs

Coffee Break

16:00-16:55 Ruth Lawrence - Symmetric sums and integrality of quantum 3-manifold invariants
17:00-17:55 Roy Meshulam - Domination numbers and homology

29 April

Lecture Hall 130: Feldman building

9:15-10:25 Yoav Segev- Finite groups acting on acyclic complexes II

Coffee Break

10:45-11:55 Sergey Fomin - Generalized associahedra and cluster algebras II
12:00-12:55 Ron Aharoni - Independent systems of representatives, a survey
14:30-15:25 Noga Alon - Spectral Techniques in Extremal Combinatorics
15:30-16:25 Ron Adin - Polytopes, face numbers, and symmetry

Coffee Break

17:00-17:55 Gil Kalai - Topological Helly-type theorems

30 April

Lecture Hall 130: Feldman building

9:15-10:25 Alexander Barvinok - Wild convex bodies II

Coffee Break

10:45-11:45 Vitali Milman - How far is an arbitrary convex body from an ellipsoid ? a geometric question considered with a computational-complexity type "ideology" (joint with the HU theoretical CS seminar)
12:00-12:55 Eli Berger- A function dual to the Lovasz Theta Function

Afternoon: excursion

1 May

Lecture Hall 130: Feldman building

9:15-10:25 Eric Babson - f-vectors II

Coffee Break

10:45-11:40 Ehud DeShalit - Hyperplane arrangements and
Harmonic Analysis on Buildings
12:00-12:55 Alex Lubotzky - Ramanujan complexes
14:30-15:40 Francesco Brenti- Combinatorics of Schubert varieties II

Light refreshments in the Mathematics building
Lecture Hall 2: mathematics building

16:00-17:00 Maria Chudnovsky - Erdos Lecture: The Strong Perfect Graph THEOREM
17:30-16:25 Emmanuel Farjoun - The fundamental groups of limits of simplicial complexes

2 May

Lecture Hall 2: mathematics building

9:15-10:10 Maria Chudnovsky - Testing for perfectness
10:20 - 11:00 Lauren K. Williams - Some combinatorics and topology related to the totally non-negative part of the Grassmannian.
11:25-12:20 Eran Nevo - Algebraic shifting and some basic constructions on simplicial complexes

coffee break
12:30-13:25 Gil Alon - Realization of the Orlik-Solomon algebra of a hyperplane arrangement on its inclusion lattice.

3 May
IAS offers an excrusion to the dead sea and Massada

4-5 May

Back in Feldman building

4 April

Lecture Hall 130: Feldman building

9:30-(?)10:40 Shmuel Weinberger - Combinatorics and Homology, Hopf conjecture in differential geometry and combinatorics (Charney-Davies and beyond) followed by
10:40(?)-12:45(?) Topology and combinatorics, discussion, thoughts, open problems, coffee
Sunday afternoon - free, unformal discussions

5 April

Lecture Hall 130: Feldman building

Convexity and optimization
Convex bodies, mathematical programming and optimization:
10:00 - 10:40 Greg Blekherman - Volumes of wild convex sets
11:00 - 11:45 Gideon Weiss - Continuous linear programming
12:00 - 12:40 Discussion, open problems, coffee

Monday afternoon - free

The lectures will be specially targeted for graduate and post-graduate
students. www.as.huji.ac.il/schools.html
www.as.huji.ac.il/schools/midrasha.pdf
http://www.ma.huji.ac.il/~kalai/mathprog03.html

Abstracts or informal descriptions of lectures: