3 papers
math.LO2025
A note on valued fields with finite group actions
Piotr Błaszkiewicz, Jakub Gogolok
We consider valued fields equipped with an action of a given finite group by automorphisms. We show that the theory of such structures admits a model companion which is axiomatized…
math.LO2024
The class of Krasner hyperfields is not elementary
Piotr Błaszkiewicz, Piotr Kowalski
We show that the class of Krasner hyperfields is not elementary. To show this, we determine the rational rank of quotients of multiplicative groups in field extensions. Our argumen…
math.FA2019
Caristi-Kirk and Oettli-Théra Ball Spaces and applications
Piotr Błaszkiewicz, Hanna Ćmiel, Alessandro Linzi +1
Based on the theory of ball spaces introduced by Kuhlmann and Kuhlmann we introduce and study Caristi-Kirk and Oettli-Théra ball spaces. We show that if the underlying metric space…