  Quantum electrodynamics (QED) produces a picture of liquid water as a mixture
of a low density coherent phase and an high density non-coherent phase.
Consequently, the Archimedes principle prescribes that, within a gravitational
field, liquid water should be made up, at surface, mainly of the coherent
fraction, which becomes a cage where the gas-like non-coherent fraction is
trapped, acquiring a non-vanishing pressure (vapor tension). Therefore, it is
possible to probe the QED picture by observing the behavior of liquid water
under reduced gravity conditions. The floating water bridge could be a useful
test model.
