Speaker
Description
Local effects in a clumpy Universe affect photon paths and give rise to non-Gaussian features in the large-scale structure. We evaluate the higher-order moments for the distribution of the luminosity distance by adopting the averaging formalism on the past light cone. We compute the skewness in the Hubble-Lemaître diagram at the leading order in the cosmological perturbative expansion of the gravitational potential. In particular, we focus on perturbations of the luminosity distance due to gravitational lensing. We discuss our findings in view of recent numerical relativistic simulations, confirming that the skewness of the distance-redshift relation primarily originates from the late-time matter bispectrum as a signature of the interplay between photons and cosmic structures.
