Two‐dimensional Topology of Large‐Scale Structure in the Las Campanas Redshift Survey

We have measured the topology (genus) of the density distribution oflarge-scale structure observed in the Las Campanas Redshift Survey (LCRS). TheLCRS is complete to magnitude 17.5, and contains nearly 24000 galaxies withmedian redshift of 30000 km/s. The large volume and large number of galaxiesallows sampling of nearly 100 independent structures with which to compute thegenus topology, a vast improvement over previous studies. We find that thegenus is consistent with a random-phase Gaussian distribution of initialdensity fluctuations, as would be produced naturally in inflationary models.When we combine these results with the genus measurements of the COBE microwavebackground fluctuations, we find that two orthogonal projections of thethree-dimensional distribution of initial density fluctuations are consistentwith Gaussian random-phase behavior, in agreement with standard inflationarymodels. Particular attention is given to statistical significance of the genustest.Comment: AASTeX, v4, preprint, 11 pages including 2 PS figure