2 citations · 3 across the 14 of their papers we have counts for
15 papers
Uncountably many maximally consistent neighborhood complete congruential modal logics
Zalán Gyenis, Krzysztof Krawczyk
We solve an open problem posed by Peter Fritz in \cite{Fritz} by proving that there are uncountably many C-Post complete congruential modal logics which are neighborhood complete.…
Two questions of Kowalski-Słomczyńska
Zalán Gyenis
That the inclusion is proper and Mod is not generated by free -algebras is proved, answering two open questions from Kowals…
Uncountably many conditionally inaccessible decisions exist in every finite probability space
Zalán Gyenis, Miklós Rédei, Leszek Wroński
In a recent paper \cite{Redei-Jing2026} the notion of conditional -inaccessibility of a decision based on utility maximization was defined and examples of conditionally -inac…
More on modal logics and deduction
Zalán Gyenis, Zalán Molnár, Övge Öztürk
We study the relation between additivity and deduction theorems in the algebraic semantics of congruential modal logic. Additivity of the modal operator is well-known to imply the…
On covers of quasivarieties of p-algebras
Zalán Gyenis
This paper characterizes the covers of varieties of p-algebras in the lattice of quasivarieties of p-algebras. In particular, it is shown that every such variety has exactly one co…
Probabilities are always axiomatizable
Zalán Gyenis
In this paper we study the interaction between logic and probability. In particular, we show that the convex hull of evaluations of a broad class of logics is always effectively ax…
Permutations, substitutions and finite axiomatizability
Hajnal Andréka, Zalán Gyenis, István Németi
Algebras of relations form an algebraic framework for the study of logical systems, extending the correspondence between Boolean algebras and propositional logic. Tarski's represen…
Substitutions of variables are finitely axiomatizable over quantifications and permutations
Hajnal Andréka, Zalán Gyenis, István Németi
This paper proves that the equational theory of the class of representable polyadic algebras is finitely axiomatizable over its substitution-free reduct , f…
Varieties of modal algebras without the congruence extension property
Zalán Gyenis, Zalán Molnár
In a recent paper, Krawczyk proved that there are continuum many axiomatic extensions of global consequence associated with the modal system that do not admit the local deducti…
Questionable and Unquestionable in Quantum Mechanics
Laszlo E. Szabo, Marton Gomori, Zalan Gyenis
According to the Kolmogorovian Censorship Hypothesis, everything that quantum theory says about the world in the language of the quantum mechanical Hilbert space formalism is actua…
Subalgebra Independence
Zalán Gyenis, Alexa Gopaulsingh, Övge Öztürk
Subobject independence as morphism co-possibility has recently been defined in [2] and studied in the context of algebraic quantum field theory. This notion of independence is hand…
Chromatic number of the product of graphs, graph homomorphisms, Antichains and cofinal subsets of posets without AC
Amitayu Banerjee, Zalán Gyenis
We have observations concerning the set theoretic strength of the following combinatorial statements without the axiom of choice. 1. If in a partially ordered set, all chains are f…
Naive probability
Zalan Gyenis, Andras Kornai
We describe a rational, but low resolution model of probability.
Categorial subsystem independence as morphism co-possibility
Zalán Gyenis, Miklós Rédei
This paper formulates a notion of independence of subobjects of an object in a general (i.e. not necessarily concrete) category. Subobject independence is the categorial generaliza…
Ultraproducts of continuous posets
H. Andréka, Z. Gyenis, I. Németi
It is known that nontrivial ultraproducts of complete partially ordered sets (posets) are almost never complete. We show that complete additivity of functions is preserved in ultra…