A counts-in-cells analysis of Lyman-Break galaxies at redshift z∼3

We have measured the counts-in-cells fluctuations of 268 Lyman-break galaxies with spectroscopic redshifts in six 9' x 9' fields at z similar to 3. The variance of galaxy counts in cubes of comoving side length 7.7, 11.9, 11.4 h(100)(-1) Mpc is sigma(gal)(2) similar to 1.3 +/- 0.4 for Omega(M) = 1, 0.2 open, 0.3 flat, implying on these scales a bias of sigma(gal)/sigma(mass) = 6.0 +/- 1.1, 1.9 +/- 0.4, and 4.0 +/- 0.7. The bias and abundance of Lyman-break galaxies are surprisingly consistent with a simple model of structure formation that assumes only that galaxies form within dark matter halos, that Lyman-break galaxies' rest-UV luminosities are tightly correlated with their dark masses, and that matter fluctuations are Gaussian and have a linear power-spectrum shape at z similar to 3 similar to that determined locally (Gamma similar to 0.2). This conclusion is largely independent of cosmology or spectral normalization sigma(8). A measurement of the masses of Lyman-break galaxies would in principle distinguish between different cosmological scenarios.