paraffin lamps may be coming back, too
Analog computing may be coming back
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Re: Analog computing may be coming back
#32The mark of a maturing domain is the evolution from only general tools to general + specialized. We've gone from only CPUs to CPU + GPU to specialized AI chips (Neural Engine, Tensor chips etc.) and specialized computing is a big tent which can fit many different architectures together. Analog computing is the closest thing to bioengineering in fundamental computer science that I know of, so I am confident that it wi…
Maybe I'm missing something, but wouldn't any optical computer have to still funnel signal through binary logic gates at some point? In what sense is that any more analog than (digital recordings on analog) magnetic tape decoded by a modem? The ultimate computation is still 1/0
Get a ruler. Draw a line 10 cm long, AB. Now grab end B and draw another another line, BC, with a certain angle $/alpha$ wrt to the first. Now measure the distance AC.
Congratulations! You have just built an analog computer to use the Law of Cosines to solve for line segment AC. Non-dimensionalize your result and its a general LofC solver. A problem that (I suspect) would take the majority of modern day Eng undergrads a week to program without the use of the math lib[1], can be solved by any keen middle schooler.
Now build a robot that measures AC for you and you have an API for your analog computer.
Typically an analog computer is thought of as a set of opamps and diodes, whose currents and voltages solve a set of non-linear ODEs; but thats a very narrow view. An analog computer is, ultimately, any physics experiment whose model is known
Wind tunnel? Navier Stokes analog computer
Cold atoms traveling through a double slit in a magnetic field? Analog Quantum computer
RCL circuit? Analog computer solving the response of a car's suspension.
[1] code reuse and libraries are a big reason why digital computers are more popular to solve models nowadays. Cost, bandwidth, are another. Ostensibly so is reproducibility. But if CS scientists cannot get reproducible builds, what hope does a humble physicist hacking on C or Matlab have?
Re: Analog computing may be coming back
#33isn't a quantum computer a kind of analog computer? Wikipedia says "An analog computer or analogue computer is a type of computer that uses the continuous variation aspect of physical phenomena" https://en.wikipedia.org/wiki/Analog_computer
Re: Analog computing may be coming back
#34Earlier quoted context omitted.
Our brains are subject to very different design constraints. Wheels are very efficient, but nature doesn't use them because the environment and the exigencies of biological reproduction and repair indicate other strategies. It really isn't a simple thing.
Interesting analogy, and I see your point. What I'm trying to say is, we know that there's way to perform certain computations that's orders of magnitude more efficient than we've ever achieved. We have a working example of it. And yet, we choose to develop a wholly different technology, from scratch, that's unproven, instead of trying to emulate or understand what already have.
We are far from having a model of how the brain really works.
Furthermore, i know it's a really common analogy but the brain is not really comparable to a computer. The brain is not programmable, it only have a single function which is "given x input, what output is more likely to keep the organism alive and well". It's a complex task, for sure.
But that's not a computer.
A computer is a machine on which you can run arbitrary programs. I can't plug some wires in your brain and program it to do what I want. It's not that the sockets for my wires are missing, it's just that the physical structure doesn't allow generic computing. If you really wanted to make an analogy, you could say that the brain is an electric circuit. You cannot program an electric circuit. It does what it's wired to do. You can't say that your electrical circuit is faster than a computer. It makes no sense.
So it's a false assumption to say that brains are faster than computers because it's just something that you cannot compare.
Re: Analog computing may be coming back
#35isn't a quantum computer a kind of analog computer? Wikipedia says "An analog computer or analogue computer is a type of computer that uses the continuous variation aspect of physical phenomena" https://en.wikipedia.org/wiki/Analog_computer
Quantum logic gates perform discrete operations on quantum states of qubits. That is there's a finite number of quantum states that qubits can end up in (in the ideal quantum computer).
Re: Analog computing may be coming back
#36Analog computing sucks. It's inherently sensitive to noise and random variation in your devices that's basically ubiquitous with modern chip-making processes. Digital electronics actively reject noise at every step in a computation, albeit at the cost of wasting energy in the process. With analog, a more complex computation becomes exponentially harder.
> inherently sensitive to noise and random variation in your devices
What is a drawback to most, can be a benefit for others.
Many like listening to LPs not because the quality is superior, but because the quality is worse.
Re: Analog computing may be coming back
#37Earlier quoted context omitted.
Maybe I'm missing something, but wouldn't any optical computer have to still funnel signal through binary logic gates at some point? In what sense is that any more analog than (digital recordings on analog) magnetic tape decoded by a modem? The ultimate computation is still 1/0
Get a ruler. Draw a line 10 cm long, AB. Now grab end B and draw another another line, BC, with a certain angle $/alpha$ wrt to the first. Now measure the distance AC. Congratulations! You have just built an analog computer to use the Law of Cosines to solve for line segment AC. Non-dimensionalize your result and its a general LofC solver. A problem that (I suspect) would take the majority of modern day Eng undergrad…
> Typically an analog computer is thought of as a set of opamps and diodes, whose currents and voltages solve a set of non-linear ODEs;
Oh oh oh! and also resistor/capacitor circuits! Great for integration or differentiation!
Integration and differentiation have interesting audio effects; maybe our ears might be one of the better analog computers.
Re: Analog computing may be coming back
#38Earlier quoted context omitted.
Analog computers are like LP records: only good for nostalgia.
Depth of sound, long term storage, ease of navigation, there are lots of reasons people prefer vinyl that aren't based in nostalgia.
Depth? You mean like a large range in available amplitudes (loud vs soft)?
Re: Analog computing may be coming back
#39Analog computing sucks. It's inherently sensitive to noise and random variation in your devices that's basically ubiquitous with modern chip-making processes. Digital electronics actively reject noise at every step in a computation, albeit at the cost of wasting energy in the process. With analog, a more complex computation becomes exponentially harder.
Analog computers are like LP records: only good for nostalgia.
[deleted]
Re: Analog computing may be coming back
#40Earlier quoted context omitted.
Get a ruler. Draw a line 10 cm long, AB. Now grab end B and draw another another line, BC, with a certain angle $/alpha$ wrt to the first. Now measure the distance AC. Congratulations! You have just built an analog computer to use the Law of Cosines to solve for line segment AC. Non-dimensionalize your result and its a general LofC solver. A problem that (I suspect) would take the majority of modern day Eng undergrad…
> Typically an analog computer is thought of as a set of opamps and diodes, whose currents and voltages solve a set of non-linear ODEs; Oh oh oh! and also resistor/capacitor circuits! Great for integration or differentiation! Integration and differentiation have interesting audio effects; maybe our ears might be one of the better analog computers.
> Integration and differentiation have interesting audio effects
An integrator is just a low-pass filter and a differentiator is just a high-pass filter, so you'll most likely get "boring" audio effects ;)