Kazushige Terui (Kyoto University), Some topics on hypersequents



Hypersequent calculus, introduced by Arnon Avron, is an extension of the ordinary sequent calculus that deals with disjunctions of sequents. Historically it has been a tool for studying intermediate logics and many-valued logics (so-called fuzzy logics), but it is interesting in its own right as a proof system with a well-behaved cut-elimination procedure.

In this talk, I will discuss some aspects of hypersequents, that could be hopefully meaningful to those who are not interested in fuzzy logics at all. The topics include: