An Information-Theoretic Perspective on Coarse-Graining, Including the Transition from Micro to Macro
Artikel i vetenskaplig tidskrift, 2015

An information-theoretic perspective on coarse-graining is presented. It starts with an information characterization of configurations at the micro-level using a local information quantity that has a spatial average equal to a microscopic entropy. With a reversible micro dynamics, this entropy is conserved. In the micro-macro transition, it is shown how this local information quantity is transformed into a macroscopic entropy, as the local states are aggregated into macroscopic concentration variables. The information loss in this transition is identified, and the connection to the irreversibility of the macro dynamics and the second law of thermodynamics is discussed. This is then connected to a process of further coarse-graining towards higher characteristic length scales in the context of chemical reaction-diffusion dynamics capable of pattern formation. On these higher levels of coarse-graining, information flows across length scales and across space are defined. These flows obey a continuity equation for information, and they are connected to the thermodynamic constraints of the system, via an outflow of information from macroscopic to microscopic levels in the form of entropy production, as well as an inflow of information, from an external free energy source, if a spatial chemical pattern is to be maintained.

information theory

microscopic

macroscopic

reaction-diffusion

entropy

pattern formation

second law

Författare

Kristian Lindgren

Chalmers, Energi och miljö, Fysisk resursteori

Entropy

10994300 (eISSN)

Vol. 17 5 3332-3351

MATHEmatics of Multi-level Anticipatory Complex Systems (MATHEMACS)

Europeiska kommissionen (EU) (EC/FP7/318723), 2012-10-01 -- 2015-09-30.

Fundament

Grundläggande vetenskaper

Ämneskategorier

Annan fysik

DOI

10.3390/e17053332

Mer information

Skapat

2017-10-08