ilya_prigogine_isabelle_stengers_alvin_tofflerbookfi-org

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IRREVERSIBILITY-THE ENTROPY BARRIER
Suppose that our knowledge of initial conditions permits us
to localize a system in a small cell of the phase space. During
its evolution, we shall see this initial cell twist and turn and,
like an amoeba, send out "pseudopods" in all directions,
spreading out in increasingly thinner and ever more twisted
filaments until it finally invades the whole space. No sketch
can do justice to the complexity of the actual situation. Indeed,
during the dynamic evolution of a mixing system, two
· points as close together in phase space as we might wish may
head in different directions. Even if we possess a lot of information
about the system so that the initial cell formed by its
representative points is very small, dynamic evolution turns
this cell into a true geometric "monster" stretching its network
of filaments through phase space.
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Figure 34. Typical evolution in phase space of a cell corresponding to a
"mixing" system. The volume is still conserved but no more its form: the cell
progressively spreads through the whole phase space.
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