We prove that a type-definable Lascar strong type has finite diameter. We answer also some
other questions from [1] on Lascar strong types. We give some applications on subgroups of …

Lascar described E KP as a composition of EL and the topological closure of EL (Casanovas
et al. in J Math Log 1 (2): 305–319). We generalize this result to some other pairs of …

. For arbitrary groups, we use Bohr neighborhoods of bounded rank and width inside normal
subgroups of bounded index. Our proofs are largely model-theoretic, and heavily rely on a …

We develop “local NIP group theory” in the context of pseudofinite groups. In particular,
given a sufficiently saturated pseudofinite structure G expanding a group, and left invariant …

We introduce the notion of first order amenability, as a property of a first order theory $ T $:
every complete type over $\emptyset $, in possibly infinitely many variables, extends to an …

The" space" of Lascar strong types, on some sort and relative to a given complete theory T,
is in general not a compact Hausdorff topological space. We have at least three (modest) …

For a group G definable in a first order structure M we develop basic topological dynamics in
the category of definable G-flows. In particular, we give a description of the universal …

We generalize the model theory of small profinite structures developed by Newelski to the
case of compact metric spaces considered together with compact groups of …

We observe simple links between equivalence relations, groups, fields and groupoids (and
between preorders, semi-groups, rings and categories), which are type-definable in an …

Les structures menues apparaissent dans les années 60 en lien avec la conjecture de
Vaught. Les structures minces englobent à la fois les structures minimales et menues. Les …