The world of light I know from daily experience doesn't fit into an optical fibre. Perhaps in other contexts the signal velocity of light does exceed C.
Harry > > http://physicsweb.org/articles/news/8/11/10/1 > > Physicists in Switzerland have confirmed that information cannot be > transmitted faster than the speed of light. Nicolas Gisin and colleagues > at the University of Geneva have shown that the "group velocity" of a > laser pulse in an optical fibre can travel faster than the speed of > light but that the "signal velocity" - the speed at which information > travels - cannot (N Brunner et al. 2004 Phys. Rev. Lett. 93 203902). > >
