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Self-Organised Criticality: Difference between revisions
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Self-Organised Criticality (SOC) is a generic concept, applicable to a host of complex systems | Self-Organised Criticality (SOC) is a generic concept, applicable to a host of complex systems | ||
<ref>[http://en.wikipedia.org/wiki/Self-organised_criticality Self-Organised Ciriticality in the Wikipedia]</ref>. | <ref>[http://en.wikipedia.org/wiki/Self-organised_criticality Self-Organised Ciriticality in the Wikipedia]</ref>. | ||
A system is said to be in this state when it is at an attractive critical point at which it behaves as in a phase transition (i.e., the spatial and temporal scales are scale-invariant, or nearly so). | A system is said to be in this state when it is at an ''attractive'' critical point at which it behaves as in a phase transition (i.e., the spatial and temporal scales are scale-invariant, or nearly so). | ||
Note that ordinary phase transitions are not attractive, and maintaining the system near such a phase transition point requires fine-tuning some system parameters. | |||
SOC is different in that the system is attracted to the critical point. | |||
This situation can only occur in systems that are ''not in equilibrium'', in which fluctuations provide a mechanism for regulating the system and keeping it close to criticality. | |||
In magnetically confined plasmas, this state is thought to be responsible for the global transport phenomena of ''profile consistency'', the ''Bohm scaling'' of confinement (in L-mode) | In magnetically confined plasmas, this state is thought to be responsible for the global transport phenomena of ''profile consistency'', the ''Bohm scaling'' of confinement (in L-mode) | ||