Sending signals to space-like separated regions

Two recent works suggest a possibility of sending signals to a space-like s eparated region, contrary to the spirit of special relativity. In the first work (J. Grunhaus, S. Popescu, and D. Rohrlich, Phys. Rev. A 53, 3781 (199 6)) it has been shown that sending signals to a particular union of space-l ike separated regions cannot cause causality paradoxes. Another work (Y. Ah aronov and L. Vaidman, Phys. Rev. A 61, 052108 (2000)) showed that the rela tive phase of the quantum superposition of a particle at two separate locat ions can be measured locally. Together with the possibility of changing the relative phase in a nonlocal way using the potential effect we, apparently , have a method of sending signals to space-like separated regions. These a rguments are critically analyzed in this paper.