Søren Brinck Knudstorp

activity

20242026

collaborators

9 papers

math.LO2026

Teams, Truthmakers, Translations

Maria Aloni, Alexandru Baltag, Johan van Benthem +2

We present a faithful translation from Aloni's logic BSL into a classical modal logic over semilattices combining ideas from earlier modal translations of truthmaker semantics with…

math.LO2026

Medvedev logic is undecidable

Rodrigo Nicolau Almeida, Søren Brinck Knudstorp

We show that Medvedev's logic of finite problems, a well-known superintuitionistic logic, is undecidable. The key method is a reduction from the periodic tiling problem to non-theo…

math.LO2026

Possibly Relevant Translations

Søren Brinck Knudstorp

We develop translations from relevant logics into normal modal logics, and use them to clarify structural connections between relevant and modal logic, obtain a few corollary resul…

math.LO2026

Undecidability in Relevant Logic

Søren Brinck Knudstorp

We prove undecidability for every positive relevant logic extending the system axiomatized by hypothetical syllogism, prefixing, and suffixing and contained in the logic of the sem…

math.LO2026

The logic of bunched implications is undecidable

Nick Galatos, Peter Jipsen, Søren Brinck Knudstorp +1

The logic of bunched implications (BI), introduced by O'Hearn and Pym (1999), has attracted significant attention due to its elegant proof calculus, varied semantics, and close con…

math.LO2025

Knocking Down Boxes: The FMP for $K \oplus □^{m + k} p \to □^{m} p$

Søren Brinck Knudstorp

It is a long-standing open problem whether modal logics of the form $K \oplus □^{n} p \to □^{m} p$ for $n > m > 1$ have the finite model property (FMP). We solve this by sho…

math.LO2025

Diamonds and Dominoes: Impossibility Results for Associative Modal Logics

Søren Brinck Knudstorp

We show that for any class of Boolean algebras with an associative operator, if it contains the complex algebra of (P(N), U), its equational theory is undecidable. Equivalently, an…

math.LO2025

Convex Team Logics

Aleksi Anttila, Søren Brinck Knudstorp

We prove expressive completeness results for convex propositional and modal team logics, where a logic is convex if, for each formula, if it is true in two teams $t$ and $u$ and $t…

math.LO2024

Tho Modal Logic of Minimal Upper Bounds

Søren Brinck Knudstorp

To formalize patterns of information increase and decrease, Van Benthem (1996) proposed modal information logic (MIL), a modal logic over partial orders. In MIL, points are interpr…

Teams, Truthmakers, Translations

Medvedev logic is undecidable

Possibly Relevant Translations

Undecidability in Relevant Logic

The logic of bunched implications is undecidable

Knocking Down Boxes: The FMP for K⊕□m+kp→□mp

Diamonds and Dominoes: Impossibility Results for Associative Modal Logics

Convex Team Logics

Tho Modal Logic of Minimal Upper Bounds

Knocking Down Boxes: The FMP for $K \oplus □^{m + k} p \to □^{m} p$