  Higher-order statistics are a useful and complementary tool for measuring the
clustering of galaxies, containing information on the non-gaussian evolution
and morphology of large-scale structure in the Universe. In this work we
present measurements of the three-point correlation function (3PCF) for 187,000
galaxies in the WiggleZ spectroscopic galaxy survey. We explore the WiggleZ
3PCF scale and shape dependence at three different epochs z=0.35, 0.55 and
0.68, the highest redshifts where these measurements have been made to date.
Using N-body simulations to predict the clustering of dark matter, we constrain
the linear and non-linear bias parameters of WiggleZ galaxies with respect to
dark matter, and marginalise over them to obtain constraints on sigma_8(z), the
variance of perturbations on a scale of 8 Mpc/h and its evolution with
redshift. These measurements of sigma_8(z), which have 10-20% accuracies, are
consistent with the predictions of the LCDM concordance cosmology and test this
model in a new way.
