Developing non-perturbative methods might be crucial for understanding inflation and its predictions. In this talk, I will present a nonlinear study of the inflationary epoch of the Universe based on numerical lattice simulations. The simulation can be used to compute the nonlinear density field predicted by inflation, allowing to understand primordial non-Gaussianity beyond the usual fnl expansion. Using some examples, I will show that the simulation can be a powerful tool for understanding the predictions of inflation, both for large-scale observables (such as large-scale structure and CMB) and small-scale observables (primordial black holes and gravitational wave backgrounds).
