Abstract
When an energetic particle collides coherently with many medium
particles at high energies, the Bose-Einstein symmetry with respect to
the interchange of the exchanged virtual bosons leads to a destructive
interference of the Feynman amplitudes in most regions of the phase
space but a constructive interference in some other regions of the
phase space. As a consequence, the recoiling medium particles have a
tendency to come out collectively along the direction of the incident
fast particle, each carrying a substantial fraction of the incident
longitudinal momentum. Such an interference appearing as collective
recoils of scatterers along the incident particle direction may have
been observed in angular correlations of hadrons associated with a
high-$p_T$ trigger in high-energy AuAu collisions at RHIC.
