WEAK MARTINGALE HARDY SPACES
Abstract: Weak martingale Hardy spaces generated by an operator are investigated. The
concept of weak atoms is introduced and an atomic decomposition of the space is
given if the operator is predictable. Martingale inequalities between weak Hardy spaces
generated by two different operators are considered. In particular, we obtain inequalities for
the maximal function, for the -variation, and for the conditional -variation. The duals
of the weak Hardy spaces generated by these special operators are characterized.
2000 AMS Mathematics Subject Classification: Primary: -; Secondary: -;
Key words and phrases: -