Institute for Advanced Study/Princeton University Early Universe/Cosmology Lunch Discussion

A key challenge for the next decade of survey cosmology is ensuring that the models for summary statistics they measure, such as galaxy clustering and lensing, are sufficiently accurate in light of the high degree of precision of these measurements. A recently proposed class of models, hybrid effective field theory (hybrid EFT), combines perturbation theory-based descriptions of the tracer--matter connection with the nonlinear dark matter distributions produced by cosmological N-body simulations. I will show how hybrid EFT promises to be a powerful model for describing the two-point statistics of clustering and lensing to small scales at high accuracy. I will proceed to survey recent developments in this juncture between simulations and perturbation theory that show their combination is mutually beneficial beyond just modelling two-point statistics.