In this article, we present a family of algorithms for linear programming based on an algorithm proposed by von Neumann. The von Neumann algorithm is very attractive due to its simplicity, but is not practical for solving most linear programs to optimality due to its slow convergence. Our algorithms were developed with the objective of improving the practical convergence of the von Neumann algo...

We provide necessary and sufficient conditions for a Gaussian ring R to be semihereditary, or more generally, of w.dimR ≤ 1. Investigating the weak global dimension of a Gaussian coherent ring R, we show that the only values w.dimR may take are 0, 1 and ∞; but that fP.dimR is always at most one. In particular, we conclude that a Gaussian coherent ring R is either Von Neumann regular, or semiher...

We show that the second cohomology group H2(M⊗N, M⊗N) is always zero for arbitrary type II1 von Neumann algebras M and N .

We discuss the local structure of the net O 7→ M(O)′′ of von Neumann algebras generated by a representation of a local gauge group C∞ c (M,G). Our discussion is independent of the singularity of spectral measures, which has been discussed by many authors since the pioneering work of Gelfand-Graev-Veršic. We show that, for type (S) operators UA,b, second quantized operators with some twists, the...

The purpose of this paper is to prove that a completely positive projection on a Hilbert space associated with a standard form of a von Neumann algebra induces the existence of a conditional expectation of the von Neumann algebra with respect to a normal state, and we consider the application to a standard form of an injective von Neumann algebra.

Amalgamated free products of von Neumann algebras were first used by S. Popa ([26]) to construct an irreducible inclusion of (non-AFD) type II1 factors with an arbitrary (admissible) Jones index. Further investigation in this direction was made by K. Dykema ([10]) and F. Rădulescu ([27, 29]) based on Voiculescu’s powerful machine ([40, 41, 44]), and F. Boca ([4]) discussed the Haagerup approxim...

Recently Chubanov proposed a method which solves homogeneous linear equality systems with positive variables in polynomial time. Chubanov’s method can be considered as a column-wise rescaling procedure. We adapt Chubanov’s method to the von Neumann problem, and so we design a polynomial time column-wise rescaling von Neumann algorithm. This algorithm is the first variant of the von Neumann algo...