Constraints on galaxy bias, matter density, and primordial non-Gaussianityfrom the PSCz galaxy redshift survey

We compute the bispectrum fur the IRAS PSCz catalog and find that the galax y distribution displays the characteristic signature of gravity. Assuming G aussian initial conditions, we obtain galaxy biasing parameters 1/b(1) = 1. 20(-0.19)(+0.18) and b(2)/b(1)(2) = -0.42 +/- 0.19, with no sign of scale-d ependent bias for k less than or equal to 0.3h Mpc(-1). These results impos e stringent constraints on non-Gaussian initial conditions. For dimensional scaling models with chi (2)(N) statistics, we find N > 49, which implies a constraint on primordial skewness B-3 < 0.35.