====== Ting Su (Hamburg) ======

====== Classification of Stringent Hypergroups and Doubly Distributive Skew Hyperfields ======

===== Abstract for the Combinatorics Seminar 2019 September 24 =====

A hypergroup is stringent if a ⊞ b is a singleton whenever a ≠ b. A hyperfield is stringent if the underlying additive hypergroup is. Every doubly distributive skew hyperfield is stringent, but not vice versa. I present a classification of stringent hypergroups, from which a classification of doubly distributive skew hyperfields follows.


----