Suarez and Gisin, quantum physicists. Nicolas Gisin (right, born 1952) works in the GAP (Group of Applied Physics) at the University of Geneva, Switzerland. Antoine Suarez (left) physicist and philosopher, moved to Switzerland from Spain. In 1997 he proposed (with Scarani) an experiment that was carried out in 2001 by Gisin and colleagues. The experiment demonstrated the breakdown of causality in quantum physics. Some quantum events can become entangled. Two particles will appear to be linked across space and time, with changes to one of the particles instantaneously affecting the other one. As it is independent of time and space, this shows that quantum effects can precede cause. Photographed in February 2003.