4 papers
Idealistic equivalence relations and the Lusin derivative
Bilge Köksal, Mateusz Lichman, Sławomir Solecki
We give a proof, that does not rely on analytic determinacy, of the existence of an idealistic analytic equivalence relation with Borel classes that is not classwise Borel isomorph…
On strong algebrability of families of non-measurable functions of two variables
Szymon Głcab, Mateusz Lichman, Michał Pawlikowski
Recently Tomasz Natkaniec in [On lineability of families of non-measurable functions of two variable. Rev. R. Acad. Cienc. Exactas Fís. Nat. Ser. A Mat. RACSAM, 115(1):Paper No. 33…
Free group of Hamel functions
Mateusz Lichman, Michał Pawlikowski, Szymon Smolarek +1
We construct a free group of continuum many generators among those autobijections of which are also Hamel bases of , with identity function included. We…
On functions preserving products of certain classes of semimetric spaces
Mateusz Lichman, Piotr Nowakowski, Filip Turoboś
In the paper we continue the research of Borsík and Doboš on functions which allow us to introduce a metric to the product of metric spaces. In this paper we extend their scope on…