Dissipative system
From Wikipedia, the free encyclopedia
- Another meaning of "dissipative system" is one that dissipates heat, see heat dissipation.
A dissipative system (or dissipative structure) is a thermodynamically open system which is operating far from thermodynamic equilibrium in an environment with which it exchanges energy, matter and/or entropy. A dissipative system is characterized by the spontaneous appearance of symmetry breaking (anisotropy) and the formation of complex, sometimes chaotic, structures where interacting particles exhibit long range correlations. The term dissipative structure was coined by Belgian scientist Ilya Prigogine, who pioneered research in the field and won the Nobel Chemistry Prize in 1977.
Simple examples include convection, cyclones and hurricanes. More complex examples include lasers, Bénard cells, the Belousov-Zhabotinsky reaction and at the most sophisticated level, life itself.
A formal, mathematical definition of a dissipative system as the action of a group on a measurable set is given in the article on wandering sets.
[edit] Quantum dissipative systems
As quantum mechanics, and any classical dynamical system, relies heavily on Hamiltonian mechanics for which time is reversible, these approximations are not intrinsically able to describe dissipative systems. It has been proposed that, in principle one can couple weakly the system, say an oscillator, to a bath, i.e., an assembly of many oscillators in thermal equilibrium with a broad band spectrum, and trace (average) over the bath. This yields a master equation which is a special case of a more general setting called the Lindblad equation that is the Quantum equivalent of the classical Liouville equation. The well known form of this equation and its quantum counterpart takes time as a reversible variable over which integrate but the very foundations of dissipative structures, imposes a irreversible and constructive role for time.
[edit] See also
[edit] References
- The dissipative systems model The Australian National University
- Davies, Paul The Cosmic Blueprint Simon & Schuster, New York 1989 (abridged— 1500 words) (abstract— 170 words) — self-organized structures.
