Lattice Structures on Banach Spaces

The general problem addressed in this work is to characterize the possible Banach lattice structures that a separable Banach space may have. The basic questions of uniqueness of lattice structure for function spaces have been studied before, but here the approach uses random measure representations for operators in a new way to obtain more powerful conclusions. A typical result is the following: If $X$ is a rearrangement-invariant space on $[0,1]$ not equal to $L_2$, and if $Y$ is an order-continuous Banach lattice which has a complemented subspace isomorphic as a Banach space to $X$, then $Y$ has a complemented sublattice which is isomorphic to $X$ (with one of two possible lattice structures). New examples are also given of spaces with a unique lattice structure.