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Updated: Oct 5, 2026

Perspectives on Neuroscience
26:41

Perspectives on Neuroscience

Published on: July 31, 2007

The authority of complexity

N Stehr1, R Grundmann

  • 1Hanse-Center for Advanced Study, University of British Columbia.

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Salt particles that have dissolved in water never spontaneously come back together in solution to reform solid particles. Moreover, a gas that has expanded in a vacuum remains dispersed and never spontaneously reassembles. The unidirectional nature of these phenomena is the result of a thermodynamic state function called entropy (S). Entropy is the measure of the extent to which the energy is dispersed throughout a system, or in other words, it is proportional to the degree of disorder of a...
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The second law of thermodynamics can be stated quantitatively using the concept of entropy. Entropy is the measure of disorder of the system.
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