  Hydrodynamical systems are usually taken as chaotic systems with fast
relaxations. It is counter intuitive for "ideal" gas to have a hydrodynamical
description. We find that a hydrodynamical model of one-dimensional $|\Phi|^6$
theory shares the same ground state density profile, density-wave excitation,
as well as the similar dynamical and statistical properties with the
Calogero-Sutherland model in thermodynamic limit when their interaction
strengths matches each other. The interaction strength g0 in the
$|\Phi|^6$theory is then the index of fractional statistics. Although the model
is interacting in Bose liquid sense, but it shows integrability with periodical
coherent evolution. We also discussed the fractional statistics emerges from
the $|\Phi|^6$ theory.
