  Coherent peripheral collisions of atomic nuclei involve electromagnetic or
long range hadronic interactions at impact parameters, where both nuclei
survive intact. Recently such ultra-peripheral collisions were observed at
RHIC. The effect of the electromagnetic field can be interpreted as a
photon-photon collision with an effective center of mass energy up to a few GeV
at RHIC. At the Large Hadron Collider the effective center of mass energy will
be increased by more than an order of magnitude. This opens new opportunities,
ranging from the study of non-perturbative QCD to the search for new physics.
