Contatto di riferimento: Barbara Simoni
Partecipanti: Prof. J. Richard Bond (Canadian Institute for Theoretical Astrophysics)
Abstract: Current CMB data show a 2-parameter compression of nearly-Gaussian early Universe fluctuations, but novel primordial non-Gaussianities may arise that are not strongly 2D CMB-constrained so far, and that may be more easily detected in 3D Large Scale Structure Surveys. LSS examples will illustrate these intermittent anomalies require new statistical methods to probe them. We have a good story, even with evidence, that all structure in the universe evolved from the diffusion of quantum-fluctuations that broke the adiabaticity of coarse-grained kinematic field trajectories during inflation. I will describe the use of highly-nonlinear pseudo-spectral lattice simulations and linear dynamical systems theory to understand the non-G possibilities. Kolmogorov-Sinai entropy is used to measure linear instabilities and coarse-grained Shannon entropy is used for classical-fluctuation generation during heating, aka bursty particle creation. This kinematical entropic picture also applies to short-lived instabilities while inflation is ongoing, and I describe in-out state lattice simulations with non-G arising from multi-field potential-surface features.