December 17 | December 18 | December 19 | December 20 | December 21 | |
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08:30-09:30 | Breakfast | Breakfast | Breakfast | Breakfast | Breakfast |

10:00-11:00 | Wagner | Jahnke (Zoom) | Newelski | Kaplan | Tsankov |

11:00-11:30 | Coffe Break | Coffe Break | Coffe Break | Coffe Break | Coffe Break |

11:30-12:30 | Kaiser | Gismatullin | Hrushovski | Ivanov | Berenstein |

12:30-14:00 | Lunch Break (lunch at 13:00) | Lunch Break (lunch at 13:00) | Lunch Break (lunch at 13:00) | Lunch Break (lunch at 13:00) | Lunch Break (lunch at 13:00) |

14:00-15:00 | Moosa | Free Afternoon and World Cup Final at 16:00 |
Chernikov (Zoom) | Rzepecki | Moconja |

15:00-16:00 | Bays | Pillay | Ramsey | Macpherson | |

16:00-16:30 | Coffee Break | Coffee Break | Coffee Break | Coffee Break | |

16:30-17:30 | Tent (Zoom) | Poster session |
Terry (Zoom) | ||

17:30-19:00 | Welcome Reception | ||||

19:00 | Dinner | Dinner | Conference Banquet | Dinner | Dinner |

Motivated by the problem of understanding higher dimensional Elekes-Szabó phenomena, we consider the spatial orchard problem on a cubic surface

Joint work with Jan Dobrowolski and Tingxiang Zou.

We study expansions of a vector space

Generalizing Newelski's work in the case of types, we investigate convolution semigroups of invariant/finitely satisfiable Keisler measures on a definable group. Under the NIP assumption we demonstrate that their Ellis group is always trivial, and describe minimal left ideals and idempotent measures under some additional assumptions.

Joint work with Kyle Gannon.

I will report recent elementary results on two topics around pseudofinite fields and metric groups:

- explicit construction of algebraic closure of some pseudofinite fields;
- on exact computation of Gromov-Hausdorff distances of some matrix groups over finite fields.

A NIP version of Szemeredi's regularity lemma, in higher dimensions, has been proved by Chernikov and Starchenko; a pseudo-finite version is due to Tao and Chevalier-Levi. In the spirit of the 'Étale site' analogy between coverings and subsets, I will formulate a (much simpler) statement that makes sense for stable theories; and hope to be able to give a complete proof. Elementary algebraic topology appears in an unexpected way.

For a countable language

Deeply ramified fields are a generalization of perfectoid fields and were introduced by Gabber and Ramero. As deeply ramified fields may admit immediate extensions, there is no hope for a classical Ax-Kochen/Ershov Theorem, and hence they have eluded model-theoretic machinery so far. In this talk, we present an AKE Theorem for certain perfect deeply ramified fields with a distiguished element t down to the pointed value group and "thickened" residue field. In particular, our Theorem applies to any perfectoid field, choosing a (pseudo)uniformizer for t. As a consequence, we obtain that the perfect hull of the henselization of

Periods are defined as integrals of semialgebraic functions defined over the rationals. Periods form a countable ring not much is known about. Examples are given by taking the antiderivative of a power series which is algebraic over the polynomial ring over the rationals and evaluate it at a rational number. We follow this path and close these algebraic power series under taking iterated antiderivatives and nearby algebraic and geometric operations. We obtain a system of rings of power series whose coefficients form a countable real closed field. Using techniques from o-minimality we are able to show that every period belongs to this field. In the setting of o-minimality we define exponential integrated algebraic numbers and show that exponential periods and the Euler constant are exponential integrated algebraic number. Hence they are a good candiate for a natural number system extending the period ring and containing important mathematical constants.

Suppose that

In joint work with Martin Liebeck and Katrin Tent, we consider primitive pseudofinite permutation groups, that is, pseudofinite group actions (

In our previous work we confirmed Vaught's conjecture for binary, weakly quasi-o-minimal theories (these include binary, weakly o-minimal theories). Our further goal was to try to eliminate the assumption of binarity (which was very significant in our analysis). In the talk we'll present several results in this direction. We'll isolate some properties which imply existence of continuum many countable models. Also we'll discuss the forking-dependence relation in this context, as it's properties play an important role in our analysis.

James Freitag and I introduced “degree of nomminimality” last year as a way of bounding how many parameters one has to consider to verify the minimality of a finite rank type. At the time we could show that in differentially closed fields (and other similar theories) this degree was bounded by the

Abstract: This is a joint work with Adam Malinowski, see http://arxiv.org/abs/2209.14838

How does the (definable) topological dynamics of a group

We work in the following combinatorial set-up.

The assumptions of Theorems 1 and 2 are dual to each other, just like their proofs. Theorem 1' was already proved in our paper in Israel J.Math. (2012).

The proofs use the dual notions of weak heirs and weak coheirs. We elaborate on them. In the stable case we provide a characterization in terms of local forking. Invoved in the proof of Theorem 1 is a variant of the Ellis structure theorem for some left-continuous semigroups that are not necessarily compact.

We recover locally compact models for arbitrary approximate subgroups by topological dynamical methods, obtaining by these means some results of Hrushovski in "Beyond the Lascar group". This involves both the ``generalized Bohr compactification" of Glasner, as well as generalizing the machinery of topological dynamics from actions on compact spaces to actions on locally compact spaces.

In joint work with Itay Kaplan and Pierre Simon, we introduce a notion of independence called GS-independence, defined in terms of generically stable partial types. We will describe a context, the class of

Every semigroup admits a universal (initial) homomorphism into a group, called the Grothendieck group. If the semigroup is an Ellis semigroup, then this homomorphism is onto and factors through Ellis groups, and in particular, for Ellis groups of automorphism or definable group actions, it seems that it might be a new model-theoretic invariant, which is a quotient of the Ellis group, but is in general distinct.

I will describe the construction of the Grothendieck group, the kernel of the homomorphism from the Ellis group and discuss some related problems and observations.

This is joint work in progress with Krzysztof Krupiński.

We discuss some general criteria to show that the automorphism group of a homogeneous structure (such as metric spaces, incidence geometries, graphs and hypergraphs) are simple groups (or have some obvious simple quotients) and extend this to some extremely amenable groups.

We present recent work, joint with J. Wolf, in which we define a ternary analogue of the order property, called the functional order properly, and show that subsets of

Affine logic is a fragment of continuous logic, introduced by Bagheri, where one allows only affine functions ℝ

I shall generalize Zilber's and Poizat's theorems on field interpretation in soluble non-nilpotent groups and linearization of group actions to the dimensional context (which includes both the finite Morley/Lascar/SU/Thorn rank context and the o-minimal context). Part of the results are joint work with Adrien Deloro.