Noncommutative Down Spaces

Abstract

Given a von Neumann algebra with a semifinite normal faithful trace, the notion of a core decreasing operator is introduced. This construction depends on a family of commuting projections called an ordered core. With these tools in place, a version of the level function of a measurable operator is introduced. The down space of a strongly symmetric space of $\ddot{I}„$-measurable operators is defined.

38 pages, no figures