[Fis] entropy

Stanley N Salthe ssalthe at binghamton.edu
Sat Jan 9 20:05:04 CET 2021


As often happens, Im mistakenly sent my response to Marcus instead of, as I
intended, to fis. I here post it to fis.

On Fri, Jan 8, 2021 at 4:00 PM Stanley N Salthe <ssalthe en binghamton.edu>
wrote:

> Stan – I am not really sure how to respond to your note. In your short paragraph
> you offer a catalogue of issues that lie far outside my view of
> information science, and I believe, the view of most other careful readers
> in information science.
>
>  – ‘Entropy applies everywhere, and always in the same way’> This argues
> that signal entropy and thermodynamic entropy are identical.
>
>     S: I would not assert this!  Signal entropy is  variety of
> possibilities, while thermo entropy is possible diversity of locations of
> dispersed photons. So, formally there is a clear matching, although in
> thermo with see dispersion, while in information we see choice of one
> position from many possibilities.
>
> I know of no other FIS member that agrees with this view. Shannon and
> Weaver (1949) themselves referred to signal entropyas ‘disappointing and
> bizarre’, bizarre expressly because it differs so clearly from classic
> notions of thermodynamic entropy.
>
>     S: It is a formal matching only.
>
> – ‘ . . . NOT problems for physicists’> Again, careful readers in physics
> know well of many force-Energy related issues. Dark energy and dark
> matter are wholly unexplained, gravity is poorly understood, no Unified
> Field Theory exists to detail force-Energy transitions or quantum-cosmic
> roles, matter/anti-matter asymmetry is yet another open issue, etc., etc.
> etc. And then wehave thermodynamic energy as ONLY one of 16 accepted
> forms of energy where the interrelations between those 16 is unclear. I
> have seen three of four times where Richard Feynman during the course of
> a lecture comments on how interesting the issue of force-energy relations
> is . . . and then promptly walk off in an entirely different direction –
> leaving that one question hanging. I chuckle every time I see it.
>
>      S: I pass on this
>
> In short, you seem to make my argument for me that ‘entropy’ is a concept
> often misused and abused, not even differentiating between signal and
> thermodynamics. Shannon in The Bandwagon (1956) cautioned against
> reckless and excess of the concept ‘entropy’ – and here we are over 60
> years later still dealing with this issue. Odd.
>
>      S: I here stress conceptual similarity, not material difference. Entropy
> is referred to in many different particular ways, depending upon the
> application of the idea of dispersion/multiplicity -- in some cases we have the
> process of dispersion (entropy production), in some choice of one from
> many existing (e,g, already 'dispersed') possibilities (going the other
> way).
>
> STAN
>
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