Noise as a Boolean algebra of sigma-fields. III. An old question of   Jacob Feldman
  The noise-type completion C of a noise-type Boolean algebra B is generally not the same as the closure of B. As shown in Part I (Introduction, Theorem 2), C consists of all complemented elements of the closure. It appears that C is the whole closure if and only if B is classical (as defined in Part II, Sect. 1a), which is the main result of this Part III. 
Boris Tsirelson
math.PR