A Hölder-type inequality for positive functionals on -algebras.
A note on approximation theorems
A note on the p-distributivity in non-Archimedean f-rings.
Non-Archimedean f-rings need not be p-distributive. Moreover, if {di|i} is a subset of a non-Archimedean f-ring and a ≥ 0, the elements a vi di and vi adi need not be equal. We prove, however, that the difference is an infinitely small element when the ring has a strong unity.
A realization of -groups
A remark on radical-semisimple classes of fully ordered groups
A strongly diagonal power of algebraic order bounded disjointness preserving operators.
Algebras and spaces of dense constancies
A DC-space (or space of dense constancies) is a Tychonoff space such that for each there is a family of open sets , the union of which is dense in , such that , restricted to each , is constant. A number of characterizations of DC-spaces are given, which lead to an algebraic generalization of the concept, which, in turn, permits analysis of DC-spaces in the language of archimedean -algebras. One is led naturally to the notion of an almost DC-space (in which the densely constant functions...
An -algebra approach to Artin’s solution of Hilbert’s Seventeenth Problem
Using lattice-ordered algebras it is shown that a totally ordered field which has a unique total order and is dense in its real closure has the property that each of its positive semidefinite rational functions is a sum of squares.
Angeordnete affine Klingenbergsche Ebenen
Angeordnete affine lokale Ternärringe und angeordnete affine Klingenbergsche Ebenen
Archimedean property of ordered semirings.
Arens regularity of lattice-ordered rings
This work discusses the problem of Arens regularity of a lattice-ordered ring. In this prospect, a counterexample is furnished to show that without extra conditions, a lattice-ordered ring need not be Arens regular. However, as shown in this paper, it turns out that any -ring in the sense of Birkhoff and Pierce is Arens regular. This result is then used and extended to the more general setting of almost -rings introduced again by Birkhoff.
Atomicity of lattice effect algebras and their sub-lattice effect algebras
We show some families of lattice effect algebras (a common generalization of orthomodular lattices and MV-effect algebras) each element E of which has atomic center C(E) or the subset S(E) of all sharp elements, resp. the center of compatibility B(E) or every block M of E. The atomicity of E or its sub-lattice effect algebras C(E), S(E), B(E) and blocks M of E is very useful equipment for the investigations of its algebraic and topological properties, the existence or smearing of states on E, questions...