By a well-known result of Cook and Reckhow [4, 12], all Frege systems for the Classical Propositional Calculus (CPC) are polynomially equivalent. Mints and Kojevnikov [11] have re...
We prove a number of consistency results complementary to the ZFC results from our paper [4]. We produce examples of non-tightly stationary mutually stationary sequences, sequences...
: It follows directly from Shelah's structure theory that if T is a classifiable theory, then the isomorphism type of any model of T is determined by the theory of that model ...
We investigate effective categoricity of computable equivalence structures A. We show that A is computably categorical if and only if A has only finitely many finite equivalence c...
Wesley Calvert, Douglas Cenzer, Valentina S. Hariz...
CITY IN ABSTRACT ELEMENTARY CLASSES WITH NO MAXIMAL MODELS MONICA VANDIEREN Abstract. The results in this paper are in a context of abstract elementary classes identified by Shelah...
A new modal logic D is introduced. It describes properties of provability by interpreting modality as a deductive closure operator on sets of formulas. Logic D is proven to be dec...
It is consistent (relative to ZFC) that each union of max{b, g} many families in the Baire space which are not finitely dominating is not dominating. In particular, it is consist...
The purpose of this paper is to present some results which suggest that the Singular Cardinals Hypothesis follows from the Proper Forcing Axiom. What will be proved is that a form ...