Abstract A logic is said to admit an equational completeness theorem when it can be interpreted into the consequence relative some class of algebras. We characterize logics admitting that are either locally tabular or have tautology. In particular, shown a protoalgebraic admits precisely has two distinct logically equivalent formulas. While problem determining whether decidable both for present...

This paper provides an algebraic reconstruction of Einstein's own argument for the incompleteness quantum mechanics -- one that he thought did not make it into EPR in order to clarify assumptions underlie understanding Einstein completeness as categoricity, sense which is a type descriptive completeness, and some various ways has been more often misconstrued.

in this paper we prove a unique common coupled fixed point theorem for two pairs of $w$-compatible mappings in $s_b$-metric spaces satisfying a contrctive type condition. we furnish an example to support our main theorem. we also give a corollary for junck type maps.