  The apparent dominance of matter over antimatter in our universe is an
obvious and puzzling fact which cannot be adequately explained in present
physical frameworks that assume matter-antimatter symmetry at the big bang.
However, our present knowledge of starting conditions and of known sources of
CP violation are both insufficient to explain the observed asymmetry. Therefore
ongoing research on matter-antimatter differences is strongly motivated as well
as attempts to identify viable new mechanisms that could create the present
asymmetry. Here we concentrate on possible precision experiments at low
energies towards a resolution of this puzzle.
