Speaker
Description
I will present a novel framework for implementing stochastic inflation on stochastic trees, modelling the inflationary expansion as a branching process. The statistical properties of the curvature perturbation and other cosmological fields are encoded within the tree structure in a manner that fully captures quantum diffusion and its non-perturbative backreaction during inflation. Stochastic trees also provide an ideal tool for the study of primordial black holes and I will show how they emerge at unbalanced nodes of the tree and how their mass distribution can be derived while automatically accounting for the “cloud-in-cloud” effect. Stochastic trees do not operate on a fixed background; instead, new spacetime units dynamically emerge as the trees unfold, naturally incorporating metric fluctuations. Their recursive nature offers exceptional numerical efficiency, and I will present the FOrtran Recursive Exploration of Stochastic Trees (FOREST) code. When applied to the “quantum-well” toy model, results reveal broad mass distributions, characterised by mild power laws that are truncated by exponential tails.
