6 papers
Maehara Interpolation in Extensions of R-mingle
Wesley Fussner, Krzysztof Krawczyk
We show that there are exactly five quasivarieties of Sugihara algebras with the amalgamation property, and that all of these have the relative congruence extension property. As a…
Interpolation in Non-Classical Logics
Wesley Fussner
This chapter surveys some of the main results on interpolation in several of the most prominent families of non-classical logics. Special attention is given to the distinction betw…
Revisiting Interpolation in Relevant Logics
Wesley Fussner, Andrew Tedder
There are exactly two maximal schematic extensions of the relevant logic R with the variable sharing property. We establish that one of them has a strong form of interpolation for…
Algebraic Proof Theory for Infinitary Action Logic
Wesley Fussner, Simon Santschi, Borja Sierra Miranda
We exhibit a uniform method for obtaining (wellfounded and non-wellfounded) cut-free sequent-style proof systems that are sound and complete for various classes of action algebras,…
Interpolation in Hájek's Basic Logic
Wesley Fussner, Simon Santschi
We exhaustively classify varieties of BL-algebras with the amalgamation property, showing that there are only countably many of them and solving an open problem of Montagna. As a c…
Amalgamation in Semilinear Residuated Lattices
Wesley Fussner, Simon Santschi
We survey the state of the art on amalgamation in varieties of semilinear residuated lattices. Our discussion emphasizes two prominent cases from which much insight into the genera…