Open AccessEvolution in complex systems
Author(s) -
Anderson Paul E.,
Jensen Henrik Jeldtoft,
Oliveira L. P.,
Sibani Paolo
Publication year - 2004
Publication title -
complexity
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.447
H-Index - 61
eISSN - 1099-0526
pISSN - 1076-2787
DOI - 10.1002/cplx.20049
Subject(s) - statistical physics , observable , complex system , punctuated equilibrium , poisson distribution , power law , relaxation (psychology) , physics , computer science , mathematics , statistics , evolutionary biology , psychology , artificial intelligence , biology , quantum mechanics , neuroscience
What features characterize complex system dynamics? Power laws and scale invariance of fluctuations are often taken as the hallmarks of complexity, drawing on analogies with equilibrium critical phenomena. Here we argue that slow, directed dynamics, during which the system's properties change significantly, is fundamental. The underlying dynamics is related to a slow, decelerating but spasmodic release of an intrinsic strain or tension. Time series of a number of appropriate observables can be analyzed to confirm this effect. The strain arises from local frustration. As the strain is released through “quakes,” some system variable undergoes record statistics with accompanying log‐Poisson statistics for the quake event times. We demonstrate these phenomena via two very different systems: a model of magnetic relaxation in type II superconductors and the Tangled Nature model of evolutionary ecology and show how quantitative indications of aging can be found. © 2004 Wiley Periodicals, Inc. Complexity 10: 49–56, 2004