Large-scale 3D galaxy correlation function and non-Gaussianity
  We investigate the properties of the 2-point galaxy correlation function at
very large scales, including all geometric and local relativistic effects --
wide-angle effects, redshift space distortions, Doppler terms and Sachs-Wolfe
type terms in the gravitational potentials. The general three-dimensional
correlation function has a nonzero dipole and octupole, in addition to the even
multipoles of the flat-sky limit. We study how corrections due to primordial
non-Gaussianity and General Relativity affect the multipolar expansion, and we
show that they are of similar magnitude (when f_NL is small), so that a
relativistic approach is needed. Furthermore, we look at how large-scale
corrections depend on the model for the growth rate in the context of modified
gravity, and we discuss how a modified growth can affect the non-Gaussian
signal in the multipoles.
