TAPIR Seminar
The statistics of galaxies and their shapes offer fascinating possibilities for probing the early universe and physics of inflation. Realizing this goal however requires a relativistic description of the connection between the initial conditions from inflation and the observed galaxies today, which is complicated both by galaxy formation and the difficulties of relativistic perturbation theory. Significant progress has been made recently in rigorous perturbative approaches (capturing the physics of galaxy formation in a finite set of bias parameters), and in disentangling physical effects from "gauge artifacts" (for example, regarding f_NL in single-field inflation). I will review the current state of theoretical understanding and describe what insights nonlinear large-scale structure can offer into the physics of inflation, both in terms of scalar modes and gravitational waves.