  The ground-state ordering and dynamics of the two-dimensional (2D) S=1/2
frustrated Heisenberg antiferromagnet Cs_2CuCl_4 is explored using neutron
scattering in high magnetic fields. We find that the dynamic correlations show
a highly dispersive continuum of excited states, characteristic of the RVB
state, arising from pairs of S=1/2 spinons. Quantum renormalization factors for
the excitation energies (1.65) and incommensuration (0.56) are large.
