Preduals of JBW*-triples are 1-Plichko spaces
Preduals of JBW*-triples are 1-Plichko spaces
We prove that the predual, $M_*$, of a JBW$^*$-triple $M$ is a 1-Plichko space (i.e. it admits a countably 1-norming Markushevich basis or, equivalently, it has a commutative 1-projectional skeleton), and obtain a natural description of the $\Sigma$-subspace of $M$. This generalizes and improves similar results for von Neumann algebras …