age-old problem that the “mapping” of these early galaxies to galaxies observed at subsequent cosmic epochs is not at all straightforward, and hence there is an unsatisfying amount of uncertainty in how to interpret what is finally being seen. Given the space densities, star-formation rates, luminosities, clustering properties, and morphologies at high redshift, coupled with what seems like overwhelming evidence of a population of mature galaxies by z~1, we have suggested that the “Lyman break” galaxies are in fact the massive galaxies of the present epoch caught in the act of forming their bulges and spheroids (7.31). This would be quite natural in the more classical picture of galaxy formation, but it is unclear (to me, at least) if the observations are still consistent with purely bottom-up hierarchical formation scenarios such as Cold Dark Matter. With the data floodgate now very much opened, it should only be a matter of time before the “truth” will be known, or, at least, we may know what is not the truth.

It is a pleasure to thank my collaborators and colleagues, Kurt Adelberger, Mark Dickinson, Mauro Giavalisco, Mindy Kellogg, and Max Pettini, for allowing me to present the results of our joint work. I would like also to acknowledge financial support from the National Science Foundation through the Young Investigator Program, as well as the Alfred P.Sloan Foundation. The Keck Observatory, without which much of the work described above would not have been possible, is operated jointly by the California Institute of Technology and the University of California, and was made possible by a generous gift from the W.M.Keck Foundation.

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