ABSTRACT
3.1 Overview and caveats
Regardless of the specific origin of structure in the Universe, its existence allows us to probe the distribution of matter on various size scales from which origin scenarios can be reconstructed. At a minimum, observations clearly show that (1) the mass in the Universe is confined to discrete units called galaxies, (2) these galaxies are not distributed uniformly but are highly clustered on a variety of size scales, and (3) there are large regions that are apparently devoid of mass. Due to this complexity, it is rather difficult to determine what represents a fair volume of sampling for this structure. Nevertheless, an accurate measurement of the mass distribution over a fair volume will provide us with observational constraints on ρ, the other cosmological parameter of interest. Furthermore, the distribution of mass on both small and large scales provides a stringent constraint on any physical theory which is used to predict the formation and growth of such structure. This is discussed in detail in Chapter 5.
