activity
20202026
most citedMost simple extensions of are undecidable

4 citations · 8 across the 11 of their papers we have counts for

collaborators

12 papers

math.LO2026

Proper varieties of distributive l-pregroups are periodic

Nikolaos Galatos, Simon Santschi

We show that every proper variety of distributive -pregroups is periodic; as a result, the subvariety lattice of the variety of distributive -pregroups decomposes into…

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…

cs.LO2025

Complexities of Well-Quasi-Ordered Substructural Logics

Nikolaos Galatos, Vitor Greati, Revantha Ramanayake +1

Substructural logics are formal logical systems that omit familiar structural rules of classical and intuitionistic logic such as contraction, weakening, exchange (commutativity),…

math.RA2025

Axiomatizing small varieties of periodic l-pregroups

Nikolaos Galatos, Simon Santschi

We provide an axiomatization for the variety generated by the -periodic l-pregroup , for every , as well as for all possible joins…

math.LO2024

Generation and decidability for periodic l-pregroups

Nikolaos Galatos, Isis A. Gallardo

In [11] it is shown that the variety of distributive l-pregroups is generated by a single algebra, the functional algebra over the integers. Here, we…

math.LO2023

Decidability of distributive l-pregroups

Nikolaos Galatos, Isis A. Gallardo

We show that every distributive lattice-ordered pregroup can be embedded into a functional algebra over an integral chain, thus improving the existing Cayley/Holland-style embeddin…

math.LO2023★ 3 cited

Gluing residuated lattices

Nick Galatos, Sara Ugolini

We introduce and characterize various gluing constructions for residuated lattices that intersect on a common subreduct, and which are subalgebras, or appropriate subreducts, of th…

math.LO2023

Unilinear residuated lattices: axiomatization, varieties and FEP

Nick Galatos, Xiao Zhuang

We characterize all residuated lattices that have height equal to and show that the variety they generate has continuum-many subvarieties. More generally, we study unilinear re…

math.RA2021

Twist structures and Nelson conuclei

Manuela Busaniche, Nikolaos Galatos, Miguel Andrés Marcos

Motivated by Kalman residuated lattices, Nelson residuated lattices and Nelson paraconsistent residuated lattices, we provide a natural common generalization of them. Nelson conucl…

math.GR2021★ 1 cited

From distributive l-monoids to l-groups, and back again

Almudena Colacito, Nikolaos Galatos, George Metcalfe +1

We prove that an inverse-free equation is valid in the variety LG of lattice-ordered groups (l-groups) if and only if it is valid in the variety DLM of distributive lattice-ordered…

math.LO2020★ 4 cited

Most simple extensions of are undecidable

Nikolaos Galatos, Gavin St. John

All known structural extensions of the substructural logic , Full Lambek calculus with exchange/commutativity, (corresponding to subvarieties of commutative residuat…

math.LO2020

Theorems of Alternatives for Substructural Logics

Almudena Colacito, Nikolaos Galatos, George Metcalfe

A theorem of alternatives provides a reduction of validity in a substructural logic to validity in its multiplicative fragment. Notable examples include a theorem of Arnon Avron th…