Temporal Bias in the Clustering of Massive Cosmological Objects

It is a well-established fact that massive cosmological objects exhibit a ``geometrical bias'' that boosts their spatial correlations with respect to the underlying mass distribution. Although this geometrical bias is a simple function of mass, this is only half of the story. We show using numerical simulations that objects that are in the midst of accreting material also exhibit a ``temporal bias,'' which further boosts their clustering far above geometrical bias levels. These results may help to resolve a discrepancy between spectroscopic and clustering mass estimates of Lyman Break Galaxies, a population of high-redshift galaxies that are caught in the act of forming large numbers of new stars.