David Hogg (NYU)

Direct measurements of the assembly of massive galaxies

The standard model of cosmology is incredibly well-tested in the linear regime. However, it is in the non-linear regime that the dark sector is most likely to reveal non-trivial dynamics. I argue that we should be using galaxy observations to construct hard tests of the standard model, and give an example of one or two such tests relating to the growth of galaxies by merging. I use data taken from the Sloan Digital Sky Survey to place very strict upper limits on the growth at late times; the consequences for the dark sector are discussed.