Probing high-redshift disks with damped Lyα systems

Evidence is presented that the damped Lyalpha absorption systems are the high-redshift (z > 3) progenitors of galaxy disks. I discuss kinematic evidence that the damped Lyalpha systems are rotating disks. I also discuss implications of the lack of metal-poor damped Lyalpha systems with line width Deltav > 100 km s(-1). I then present new evidence stemming from correlations between element-abundance ratios and [Fe/H], which connects damped systems to the thick stellar disk of the Galaxy. I discuss the connections between damped Lya systems and Lyman break galaxies, and how [C II] 158 mum emission from damped Lya systems discriminates among competing theories of galaxy formation.