The Complexity and Information Content of Simulated Universes
  The emergence of a complex, large-scale organisation of cosmic matter into
the Cosmic Web is a beautiful exemplification of how complexity can be produced
by simple initial conditions and simple physical laws. In the epoch of Big Data
in astrophysics, connecting the stunning variety of multi-messenger
observations to the complex interplay of fundamental physical processes is an
open challenge. In this contribution, I discuss a few relevant applications of
Information Theory to the task of objectively measuring the complexity of
modern numerical simulations of the Universe. When applied to cosmological
simulations, complexity analysis makes it possible to measure the total
information necessary to model the cosmic web. It also allow us to monitor
which physical processes are mostly responsible for the emergence of complex
dynamical behaviour across cosmic epochs and environments, and possibly to
improve mesh refinement strategies in the future.
