The Complexity and Information Content of Simulated Universes
Franco Vazza
备注：
26 pages, 10 figures. Preprint version of chapter accepted for "Intelligent Astrophysics", published in the book series https://www.springer.com/series/10624 "Emergence, Complexity and Computation (Editors I. Zelinka, M. Brescia & D. Baron)
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.
Black hole is called optimal if information content is minimal at the University region, consisting of usual substance and one(n) black hole(s). Optimal black hole mass does not depend on the mass of the Universe region. Optimal black holes can exist when at least the two types of substance are available in the Universe: with non-linear and linear correspondence between information content and mass. Information content of optimal black hole is proportional to squared coefficient correlating information content with mass in usual substance and in inverse proportion to coefficient correlating in…
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Cosmic topology. Part Va. Information content of the observable Universe
Case Western Reserve University（凯斯西储大学）；Sofia University ``St Kliment Ohridski''（索非亚大学）；Imperial College London（帝国理工学院）；University of Pittsburgh（匹兹堡大学）；University of Toronto（多伦多大学）；Institute of Theoretical Astrophysics（理论天体物理研究所）
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