BROWNIAN MOTION
| Collection | International Encyclopedia of Systems and Cybernetics |
|---|---|
| Year | 2004 |
| Vol. (num.) | 2(1) |
| ID | ◀ 341 ▶ |
| Object type | Discipline oriented, Epistemology, ontology or semantics |
The random motion at microscopic level of particles suspended in a liquid or a gas.
As stated by P. DAVIES: “Brownian motion is the archetypical, random unpredictable process. Yet, so the argument ran, if we could follow in detail the activities of all the individual molecules involved, Brownian motion would be every bit as predictable and deterministic as clockwork. The apparent random motion of the Brownian particle is attributed solely to the lack of information about the myriads of participating molecules, arising from the fact that our senses are too coarse to permit detailed observation at the molecular level” (1990, p.49).
However: “Two major developments of the 20th century have… put paid to the idea of a clockwork universe” (Ibid).
The first was quantum mechanics which introduced indeterminacy at the physical microlevel as well as in relation to our possibility of observation . And the second one is chaos which, while still somehow deterministic, rapidly makes even very simple simple systems fairly unpredictable.
Thus, determinism cannot be polarly opposed to randomness, nor is unpredictability simply a result of our imperfect perceptions.