
General purpose analog computer - ch
https://en.wikipedia.org/wiki/General_purpose_analog_computer
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benten10
Introduced by Claude Shannon, the father of modern information theory, as we
know.

Ahhh Shannon. The guy who invented the entire field of digital freaking
electronics for his master's thesis [1], and then moved on to even greater
things. This was it seems five years after his Master's thesis. He was 25 when
he proposed this.

The bane of every grad student. "Shannon invented digital electronics for
master's thesis. Come up with anything interesting yet?" Add to this, he also
appears to have been located at Medford. The shame. What have y'all been upto
lately, Boston/Cambridge area grad students? : (

I wonder if our obsession with profits and quick returns and 'hacker culture'
is distracting people like him from making similarly great contributions?

[1]
[http://www.cs.virginia.edu/~robins/Shannon_MS_Thesis.pdf](http://www.cs.virginia.edu/~robins/Shannon_MS_Thesis.pdf)

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auvi
As Peter Thiel said, "We wanted flying cars, instead we got 140 characters."

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aswanson
I have been wondering recently if analog computing would make more sense for
certain search algorithms, like protein folding simulations. Basically, let a
set of potentials be placed in the op amp setting representing position, and
let them miller integrate the surronding charges and watch it evolve.
Basically, physical modelling directly. Im not sure of the state of analog
device precision, drift, and temp stability these days but it might be worth a
try.

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nickpsecurity
Take a look at these, esp math coprocessor:

[https://www.schneier.com/blog/archives/2015/07/friday_squid_...](https://www.schneier.com/blog/archives/2015/07/friday_squid_bl_488.html#c6701962)

The trick is using analog circuits for just what it's good for. The digital
does the rest. Need to have them integrated well. Good news is analog works
well with inexpensive process nodes like 350nm and digital stuff on them is
inexpensive. Tekmos even can integrate 90nm digital with 350nm analog plus
MPW's to keep things cheaper.

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malux85
It is my dream one day - to sell my startup, and get some form of mechanical
computer, and have it in my house as an art display.

I would like to integrate it somehow to my existing systems - so that, no
matter how little it can contribute, it can click and clack away.

I shall name him Switch

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jonsen
Wouldn't Clutch be a better name? I mean if you litterally mean mechanical.

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jacquesm
Switches were mechanical long before they were electrical. And I don't mean
'electro-mechanical', no just mechanical. Think of where the name 'railroad
switch' comes from. That lever by the side of the road is the switch (the
thing itself is called a 'point').

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maljx
Analog computer I saw in Berlin a few weeks ago, very cool stuff -
[https://twitter.com/maljx/status/650690241574080512](https://twitter.com/maljx/status/650690241574080512)

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JonnieCache
If this interests you, you may enjoy modular synthesizers, eg:
[http://www.makenoisemusic.com/maths.shtml](http://www.makenoisemusic.com/maths.shtml)

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LeoPanthera
I recommend the docu-movie "I dream of wires". I think it's on Netflix.

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gshubert17
I worked with a medium-sized analog computer in the mid 1970s. It may have had
around 20 op-amps, covered a desktop, and used an HP XY-plotter for output. I
could set up different models of differential equations. I remember simple
harmonic oscillators and predator-prey models [0]. I was studying physics
rather than computer science and didn't then know about Turing computability.
I found the GE BASIC timesharing system easier to program and use than the
analog computer, but the graphical output of the analog system was much nicer.

[0]
[https://en.wikipedia.org/wiki/Lotka%E2%80%93Volterra_equatio...](https://en.wikipedia.org/wiki/Lotka%E2%80%93Volterra_equations)

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nickpsecurity
There's been lots of practical work on this including a math coprocessor with
100x claimed acceleration. I posted a list of links below for general purpose
analog:

[https://www.schneier.com/blog/archives/2015/07/friday_squid_...](https://www.schneier.com/blog/archives/2015/07/friday_squid_bl_488.html#c6701962)

The field has more potential than most think. Needs more research. One angle I
thought about was applying it to neural networks somehow. Turns out there's a
Deep Learning company doing that right now. ;) Many possibilities left to
explore.

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aswanson
I thought I was the only one think along these lines. This field has
incredible potential...I honestly think there is an Intel-level (or greater)
company waiting to be built out of this line of research.

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angdis
Every once in a while, I hear about FPAA's (field programmable _analog_
arrays), but the concept never seems to take off despite serious efforts, even
by Motorola in the 90's.

Isn't the GPAC the same thing?

I suppose the reason these aren't popular is because the use-cases are rather
narrow (or at least usually implementable with an ordinary digital approach)?

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nickpsecurity
By not take-off, I'm guessing you just mean there's not many people buying
these:

[http://www.anadigm.com/fpaa.asp](http://www.anadigm.com/fpaa.asp)

