Wednesday, May 12, 2010

Another one

In an order complete Banach lattice: is any finite-rank positive operator approximable by positive operators having their range in finite-dimensional sublattices?

Nielsen seems to say yes, but I could not repeat the proof.

Wednesday, May 5, 2010

Stupid math question of the day

Sometimes, there are questions that seem to be fairly simple, yet I can't find the answer anywhere:


Will a vector sublattice of a Riesz space generated by a finite set be finite-dimensional?