[sdiy] slightly ot: Chua circuit and chaos

[Czech Martin]

I'm just reading a book a second time, just to make sure I understand.
The statement of this book is shocking:

there is no real chaos in physics, it is only the models
that can act chaotic. This topic was covered before,
even by the "inventor" of numerical chaos, Lorentz.

The tite is: "Der SchmetterlingsDefekt"

or the butterfly Defekt

http://www.amazon.de/exec/obidos/ASIN/3608943226/028-0134132-1666121

It seems to be not translation or summary of other english
texts (which is quite often the case).

I think the autor (Mr. Wehr) has done a good job
showing how parasites take up a new fashion of science
and draw more then speculative statements out of it.
He also shows what huge methodical questions come up
if physics takes place in the computer and not
in the lab any more. Questions like: 
can we trust computer simulations, if different operation systems
and hardware bring very different results for the same problem?
Are real numbers a correct model for physicl quantities?

m.c.




-----Original Message-----
From: harrybissell [mailto:harrybissell at prodigy.net]
Sent: Sonntag, 9. Februar 2003 19:01
To: music.maker at gte.net
Cc: synth-diy at dropmix.xs4all.nl
Subject: Re: [sdiy] expo accuracy? or integrator accuracy?, or both?


sort of like....

"I built the Chua oscillator but the result seems chaotic to me... what am I
doing wrong ?"

:^P   <bald mode off>

H^) harry (who was going to build a chua oscillator... till I heard an MP3 of one
in use...
I can barely stand the chaos of an MS-20 filter in self-oscillation..)

Scott Gravenhorst wrote:

> Grant Richter <grichter at asapnet.net> wrote:
> >> I've had an ASM-1 VCO measure in at a 21 octave range, but the last part
> >> wasn't
> >
> >That would be about 6 decades or 10E-9 to 10E-3 from the current source.
> >
> >That should be normal for an exponential pair, but of course a current of
> >10E-9 can easily leak away or be absorbed by bias currents.
> >
> >Rather than perfecting the a "good enough" core, wouldn't it be more
> >interesting to investigate new dynamic waveshaping designs like the Buchla
> >Music Easel?
> >
> >It seems to me the frequency stability is acceptable, but new timbral design
> >has barely been touched on. Timbre is arguably the next most important
> >parameter after pitch is satisfactory.
>
> Hear hear!  Does "dynamic waveshaping" mean "ever changing" or in our world,
> voltage controlled ?  I would love to play more with this.  I've done the
> usual messing with VCO sync, PWM and a bit of folding, but not much more.
> Bifurcation, as in the Chua chaos oscillator system, looks cool, but the Chua
> seems too "out of control" for my use.
>
> =========================================================
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> - Government: The other religion.
> - The media's credibility should always be questioned.
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>
> -- Scott Gravenhorst | LegoManiac / Lego Trains / RIS 1.5
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