[FRIAM] Any non-biological complex systems?

[glen ☣]

On 05/26/2017 04:54 PM, Stephen Guerin wrote:
> I am listening to Russ. I do think he's defining a sub-class of complex
> systems (eg living systems). I would like to keep the definition of
> "complex systems" broader than that though.

OK.  But I don't think he's necessarily _asserting_ that only living systems are complex systems.  He's just asking the question and engaging in a discussion wherein we might be able to refine his sub-category so that it includes physical systems.

> I understand the subtle distinction your trying to make. I would say the
> full phase space of a *complex system* has narrow critical regimes in their
> behavior (phase) space where *complex behavior* is observed as the control
> parameters are swept through the phase transition. In the critical regime
> we see complex behavior like sensitivity to initial conditions, critical
> slowing down, critical fluctuations, power law statistics, long-range
> correlations, etc. On either side of the phase transition (eg sub-critical
> and super-critical) regimes, these statistics and behaviors are not present.
> 
> That said, while the critical regime may be narrow in phase space many of
> these system "self-tune" to the critical point but that's another thread.
> 
> Agreed?

Not quite.  If these systems merely contain subsystems capable of exhibiting complexity, then those 3 you listed are not complex systems.  They are "subsystems capable of exhibiting complexity".  So, no.  They are not complex systems in isolation.  Russ' question, I think, targets naturally occurring, whole complex systems.

Now, if we add the experimental apparatus that, eg, maintains a ZB reaction for a long time, then that _whole_ system can be called a complex system.  But there's significant meat to the controlling subsystem ... and we biological creatures instantiated it.  The case is the same with, say, glycolysys.

All you need do is identify the circumstances where those three processes (ferromag, benard cells, BZ reactions) occur in nature and then we might be able to identify the systems in which they sit.  Then we can test them against whatever predicate we want.

-- 
☣ glen