Yaron Ostrover Day at TAU
Friday, June 5th, 2026, 9:45–13:30
School of Mathematical Sciences
Tel Aviv University
Schreiber Bldg Room 006
Poster
Schedule
| 9:45–10:00 | Morning coffee and refreshments |
| 10:00–10:15 | Opening remarks |
| 10:15–11:05 | Bo’az Klartag |
| 11:20–12:10 | Shira Tanny |
| 12:10–12:40 | Coffee and refreshments |
| 12:40–13:30 | Gil Kalai |
Speakers, Titles and Abstracts
Bo’az Klartag
Title: The unreasonable effectiveness of the convexity assumption in high dimensions
We survey progress from the past five years on the distribution of mass in high-dimensional convex bodies and in probability distributions with convexity properties. The concentration of measure phenomenon has traditionally been studied in highly regular or structured settings, such as spheres, Hamming cubes, Gaussian measures, Markov chains, and martingales. It turns out that convexity assumptions provide an alternative source of regularity in high dimensions with remarkably similar features: Lipschitz functions are highly concentrated, the isoperimetric problem is nearly saturated by half-spaces (up to logarithmic factors), and the central limit theorem is nearly as strong as in the setting of independent random variables. The main developments discussed include the resolution of Bourgain’s slicing problem and the Variance Conjecture, as well as recent progress on the isoperimetric problem for high-dimensional convex bodies. Based on joint work with P. Bizeul and J. Lehec.
Shira Tanny
Title: Creating Periodic Orbits: A Question of Poincaré
An old question of Poincaré asks whether periodic points can be created by small perturbations of a dynamical system. While this question was initially studied in the 1960s, various facets of it remain largely open. Recently, tools from modern symplectic topology have been used to study this question in the setting of Hamiltonian diffeomorphisms arising from classical mechanics. I will discuss a variant of this problem, based on joint work with Erman Cineli and Sobhan Seyfaddini.
Gil Kalai
Title: The 3ᵈ conjecture
The 3ᵈ conjecture (1989) asserts that
Conjecture: Let P be a centrally symmetric d-dimensional polytope. Then P
has at least 3ᵈ non-empty faces.
Equality holds for all Hanner polytopes. These are obtained from intervals
by repeatedly applying two operations: (a) Cartesian product, and (b)
passage from a polytope P to its polar dual P∗, in all possible
combinations.
The conjecture is related to earlier results of Figiel, Lindenstrauss, and
Milman (1979), Bárány and Lovász (1982), and Stanley (1986). It also has
subtle connections to Mahler’s famous 1939 conjecture, which in turn is
related in intriguing ways to Viterbo’s 2000 conjecture.
These connections lead to the geometry of normed spaces, isoperimetric
inequalities, symplectic geometry, Finsler geometry, and more. Some of
these directions have been explored in recent years by researchers from Tel
Aviv, together with international collaborators—including our birthday
honoree.
I will describe several related results and open problems, focusing mainly
on the combinatorial side.
Location
School of Mathematical Sciences, Tel Aviv University, Schreiber Building, Room 006.
Tel Aviv University campus, Ramat Aviv, Tel Aviv.
Parking
Parking is available (7:00-14:00) at the Nature Museum parking lot across from the School of Mathematical Sciences.
A sticker for free parking will be provided at the event. Please bring the parking ticket with you.