Mapping the Universe: Slices and Bubbles.

The history of map making in general is briefly reviewed, and then attention is given to past and current efforts to map portions of the universe. It is noted that the fundamental question posed by astronomers is the issue of the size of the structures in the distribution of galaxies. The cataloguing of the positions of galaxies on the sky is discussed. It is noted that velocities of galaxies are measured by examining their spectrum, or the amount of light they emit at each color or wavelength. The processes of measuring a typical redshift and plotting the subsequent data to record the positions of galaxies in a map are described. Modeling of the cosmic structure is explained and other surveys reviewed. The development of large voids and sheets in the universe is debated and the implications of the presence of dark matter discussed. The mapping of earlier universes is also considered.