  Bose-Einstein correlations of identical pions produced in high-energy pp
collisions at the LHC allow a probe of the Pomeron exchange mechanism. The size
of the domain which emits the pions depends on the multiplicity of events, but
not on the collider energy. This confirms the universal structure of Pomeron
exchange. The data at relatively low multiplicities indicate that the size of
the source created by one-Pomeron exchange is much less than the size of the
proton.
