4 papers
On the decomposition of a strong epimorphism into regular epimorphisms
Yuto Kawase, Hayato Nasu
Strong epimorphisms and regular epimorphisms are two important classes of morphisms, and they do not coincide in general. Yet, in a locally presentable category, it is known that a…
Double categories of profunctors
Yuto Kawase
We characterize virtual double categories of enriched categories, functors, and profunctors by introducing a new notion of double-categorical colimits. Our characterization is stri…
Relativized universal algebra via partial Horn logic
Yuto Kawase
Algebraic theories, sometimes called equational theories, are syntactic notions given by finitary operations and equations, such as monoids, groups, and rings. There is a well-know…
Filtered colimit elimination from Birkhoff's variety theorem
Yuto Kawase
Birkhoff's variety theorem, a fundamental theorem of universal algebra, asserts that a subclass of a given algebra is definable by equations if and only if it satisfies specific cl…