I'm not sure mathematicians are a help or a hindrance here. We think of
flow as associated with a vector field, and are quite willing to have
heat, curvature, money, optimality, etc. "flow" by moving along the
integral curves (flow lines) via the local diffeomorphisms that (we
say) actually comprise "the flow." I guess we agree that one must have
something ("stuff") to flow, but are willing to be quite abstract
about what is something. We'd certainly be willing to have concepts
flow, for example, either as transmission or as modification.
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Phil Parker Internet: pparker@twsuvm.uc.twsu.edu
Math. Dept., Wichita St. Univ. Bitnet: pparker@twsuvm
I find [in mathematics] a wonderful beauty. This is no science, this is
art, where equations fall away to elements like resolving chords, and
where always prevails a symmetry either explicit or multiplex, but always
of a crystalline serenity.---Turjan of Miir (Jack Vance)