The four uniform completions of a unital archimedean vector lattice

Abstract: In the category (\mathbf{V}) of unital archimedean vector lattices, four notions of uniform completeness obtain. In all cases completeness requires the convergence of uniformly Cauchy sequences; the completions are distinguished by the manner in which the convergence is regulated. Ordinary uniform convergence is regulated by the canonical unit (1). Inner relative uniform convergence, here termed iru-convergence, is regulated by an arbitrary positive element. Outer relative uniform convergence, here termed oru-convergence, is regulated by an arbitrary positive element of a vector lattice containing the given object as a sub-vector lattice. *-convergence is equivalent to ordinary uniform convergence on certain specified quotients of the vector lattice. In each case the complete objects form a full monoreflective subcategory of (\mathbf{V}), denoted respectively (\mathbf{ucV}), (\mathbf{irucV}), (\mathbf{orucV}), and (\mathbf{*cV}). In this article we provide a unified development of these completions by means of a novel pointfree variant of the classical Yosida adjunction.