Measuring large-scale structure from redshift surveys

Observations of the large-scale distributions of galaxies in the universe indicate the presence of very large wall-like superclusters. In their distributions there is growing evidence that there is a characteristic scale in excess of 100 h(-1) Mpc. This scale is rather interesting since it is too small to be well measured from fluctuations in the cosmic microwave background, but at the same time is large enough to be easily sampled in current redshift surveys. There are several physical processes in the universe at around recombination (equality of matter and radiation, the sound horizon, the recombination) that may have left an imprint on the fluctuation spectrum even in the galaxy distribution. We discuss how ongoing large-scale redshift; surveys may be optimally analysed, via the Karhunen-Loeve method, to provide high-precision information on the fluctuations on these interesting scales. These large surveys are the first where the dominant source of noise is systematic errors, requiring novel techniques of statistical analysis.