Self-organized criticality: Difference between revisions

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'''Self-organized criticality (SOC)''' is one of a number of [[physics|physical]] mechanisms believed to underly the widespread occurrence of certain complex structures and patterns observed in nature, such as [[fractal]]s, [[power law]]s and [[1/f noise]].  Technically speaking, it refers to (classes of) [[dynamical system]]s which have a [[critical point (physics)|critical point]] as an [[attractor]].  Their macroscopic behaviour thus displays the spatial and/or temporal [[scale invariance|scale-invariance]] characteristic of the [[critical point (physics)|critical point]] of a [[phase transition]], but without the need to tune control parameters to precise values.
'''Self-organized criticality (SOC)''' is one of a number of [[physics|physical]] mechanisms believed to underly the widespread occurrence of certain complex structures and patterns observed in nature, such as [[fractal]]s, [[power law]]s and [[1/f noise]].  Technically speaking, it refers to [[dynamical system]]s which have a [[critical point (physics)|critical point]] as an [[attractor]], resulting in the natural evolution of spatial and temporal [[scale invariance]] without the need to tune control parameters to precise values.


The phenomenon was first identified by [[Per Bak]], [[Chao Tang]] and [[Kurt Wiesenfeld]] (BTW) in a seminal paper published in [[1987]] in ''[[Physical Review Letters]]''.  These and related concepts have been enthusiastically applied across a diverse range of fields and topics, notably including [[earthquakes]] and other [[geophysics|geophysical]] problems, [[evolution|biological evolution]], [[solar flares]] and the [[econophysics|economy]].
The phenomenon was first identified by [[Per Bak]], [[Chao Tang]] and [[Kurt Wiesenfeld]] (BTW) in a seminal paper published in [[1987]] in ''[[Physical Review Letters]]'' and its concepts have been enthusiastically applied across a diverse range of fields and topics, ranging from [[earthquakes]] and other [[geophysics|geophysical]] problems to [[evolution|biological evolution]], [[solar flares]] and the [[econophysics|economy]].


SOC is typically observed in slowly-driven [[non-equilibrium thermodynamics|non-equilibrium]] systems with extended [[degrees of freedom (physics and chemistry)|degrees of freedom]] and a high level of [[nonlinearity]].  Many individual examples have been identified since BTW's original paper, but to date there is no known set of general characteristics that ''guarantee'' a system will display SOC.
SOC is typically observed in slowly-driven [[non-equilibrium thermodynamics|non-equilibrium]] systems with extended [[degrees of freedom (physics and chemistry)|degrees of freedom]] and a high level of [[nonlinearity]].  Many individual examples have been identified since BTW's original paper, but to date there is no known set of general characteristics that ''guarantee'' a system will display SOC.

Revision as of 12:59, 14 February 2007

Self-organized criticality (SOC) is one of a number of physical mechanisms believed to underly the widespread occurrence of certain complex structures and patterns observed in nature, such as fractals, power laws and 1/f noise. Technically speaking, it refers to dynamical systems which have a critical point as an attractor, resulting in the natural evolution of spatial and temporal scale invariance without the need to tune control parameters to precise values.

The phenomenon was first identified by Per Bak, Chao Tang and Kurt Wiesenfeld (BTW) in a seminal paper published in 1987 in Physical Review Letters and its concepts have been enthusiastically applied across a diverse range of fields and topics, ranging from earthquakes and other geophysical problems to biological evolution, solar flares and the economy.

SOC is typically observed in slowly-driven non-equilibrium systems with extended degrees of freedom and a high level of nonlinearity. Many individual examples have been identified since BTW's original paper, but to date there is no known set of general characteristics that guarantee a system will display SOC.

Overview

Examples of self-organized critical dynamics

Theoretical models

Empirical observations

See also

References