Water Computing

Andrew_Cronin writes "This is a nice project that some one did at MIT on building some logic computation systems without using electrons.. So why not use water..."

Comments

Very good

[Istealmymusic]

I remember of Neal Stephenson's Cryptonomicon, where when L.P.Waterhouse was walking amongst the beach at sundown, in a starlit avenue, and he drew lines in the sand. This was inspiration for barcodes, but that's beside the point. The point is Stephenson had the narrator narrate L.P.Waterhouse notice how the ocean is a Turing machine, it interacts with the sand, due to certain mathematical fluidity properties, to leave an indentation of predictable properties.

I've considered water-based computation long ago, but hats off to this student for logic design and implementation. My idea was to have water push open another wate gate, much like a flow-controlled valve, allowing for a water-based transistor. Combine this with other transistors, and you can build virtually any gate--I take that back, any gate you want. XOR and AND are good choices, as with a XOR a you can get NOT, to make a NAND, and as we all know NAND is the Univesal Binary Gate.

Re:Very good

[Idarubicin]

NAND is the Univesal Binary Gate.

In principle, couldn't XOR be used to construct all the other gates as well? Who needs a NAND explicitly? You can make an AND from XORs. An as stated, you can also get a NOT from XORs.

Yes, of course you can build up all the NANDs you need from XORs, and then use those composite gates to build the rest of the gates--but it's more efficient to skip the middle step of constructing the NANDs.

Who else tried this?

[thekernel32]

I really remember seeing a documentary on how the russians tried using water logic for computations and got pretty good with it back in the 40's. Then again they did alot of cool stuff over in that part of the world. They actually managed to stick with 50's technology for 40 years. yay communism! I knew someone who had no more after the berlin wall came down just because his job was dependent upon the crappy stuff they made breaking down. Reliable products from the west caused alot of people to loose their jobs.

I know it's an off topic rant, wanna give me some points for being interesting anyway?

Re:Cool...but an old concept

[friscolr]

In "The Way Things Work" (1988) David Macaulay also illustrates logic gates as plumbing in a building. It's on page 333 of the original book; the newer version even has an interesting rant about Bill Gates.

i always liked old school water clocks.

i seem to recall something about logic gates or some sort of logic being built out of matchboxes and beans. it played tictactoe, deciding the best move by plopping out a bean of a certain colour? i can remember neither the details nor the source.

so many youngsters

[Anonymous Coward]

Why logic gates? you can go straight to integration and computing outcomes of complex systems using water in analog circuit - some uk bunch did it back in the 50's or so for modelling the economy - and was used for such - and was still better at numerical answers for the problem until well into the 70's.

Log gate implementation

[matman]

I wonder if it would be possible to create such gates that function on water pressure changes. It's quite quick to propigate a wave through water. I'm talking about pressurizing water inside of the system, and then inducing shock waves from your inputs. Could you make gates that trigger on those pressure changes? You could probably get quite a few bps (by creating shock waves in the water) I wonder if you could just use plain old speakers to generate sound waves... I wonder what the attenuation characteristics of water are.

Only digital water logic, why not analog too

[obiwan2u]

Why not extend the metaphor...

Inductance is the same as momentum. You could build a gadget that has a turbine in the water flow with a fly wheel attached. The gadget would resist water flow starting up, and would resist the water flow slowing down once it's moving. (same as an inductor fighting a change in current)

Capacitance is the same as a flexible membrane across the pipe, which will transmit AC changes in pressure, but not DC.

You could build a capacitor/inductor tuned circuit that either filters or passes certain frequency water waves

Also, water transistors should be fun. A small flow or pressure of water controls a larger flow or pressure (in either an analog or digital fashion)

It would be a way fun tool for teaching electronics.

Re:Without electronics...

[Idarubicin]

Except, of course, that assertion involves simplifying assumptions, too.

We could go as far as high school chemistry and decide that there are 2 core 1s electrons definitely associated with the oxygen, plus four more electrons that are part of lone pairs on the oxygen (probably also mostly belonging to the oxygen atom). Then there's four electrons involved in the two sigma bonds joining the oxygen to the hydrogen. Simplest story is that it shares two with each hydrogen.

If we break out the molecular orbital theory, then it starts to get kind of messy. At the lowest level, we have a really ugly n-body problem. We can't solve the Schrodinger equation analytically for this case, so we're limited to approximate numeric solutions. (Technically, we should really account for relativistic effects and use the Dirac equation, but that's overkill for lightweight atoms like these.)

Even then, solving for the wavefunctions by whatever method only gives us a probability that electrons will be located nearest a given atom. In principle, occasionally all 10 electrons could actually be closest to one of the protons, but you would have to wait a loooooong time for it to happen.

Oh, yes--if I wanted to be picky, I could also mention that pure water will still undergo spontanous autoionization to form H+ (H3O+, actually) and OH- ions, containing the same number of electrons, but now the wrong number of protons...

One more, then I'm done. Liquid water actually tends to get kind of clumpy. In the so-called 'flickering cluster' model, water molecules in the liquid phase form short-lived hydrogen bonded clumps containing several (or even several tens of) water molecules. These clumps have an electron count that depends (of course) on their size.

Water is actually an incredibly interesting beast, chemically speaking. We take it for granted because it is ubiquitous, but there is a tremendous amount of very interesting stuff that it can do.

Hydraulic Computers: already done, isn't it?

[Anonymous Coward]

Haven't there been hydraulic control systems already for very many years?

The way that Op Amps work is mirrored by the way that hydraulic elements work. Op Amps can be used to make transisters, and thus so too can hydraulics. Transisters are used for computers.

This is not news to anyone who has studied computing.

And just as a point: Of course a water computer uses electrons. H2O has two electrons from the hydrogen and 8 from the oxygen. So each molecule uses 10 electrons. You can't get away from using electrons.

Keynes

[Zeinfeld]

The idea predates the electrical computer. In the 1930s John Maynard Keynes had a water computer that was used to construct a model of the British economy. The computer stretched over a large country mansion.

Konrad Zues' Z1 and Z2 machines were built somewhat later but used many of the same ideas, only in a much more compact space.

Of course now we will have a bunch of idiot libertarians blasting Keynes. However Keynes and his computer are the reason why Britain pulled out of the depression before the war while in the US depression turned to slump. The problem came when Keynsianism became an idelology after his death, the solution to every problem was deficit spending, just like today some idiots think that the solution to every problem (including a deficit) is tax cuts.

Re:Cool...but an old concept

[martyb]

i seem to recall something about logic gates or some sort of logic being built out of matchboxes and beans. it played tictactoe, deciding the best move by plopping out a bean of a certain colour? i can remember neither the details nor the source.

I've seen it in a book by Martin Gardner, the game was called Hexapawn. A quick search on google should turn up more details.

Interesting! In short: it's an exhaustive search of all moves from black's perspective whereby all moves are initially possible and a loss causes the last move to be removed as a choice. I found the info here. There's more at the site including how to implement it programatically.

Here's their explanation of the matchbox version of the game:

Gardner's machine is implemented as a set of 24 matchboxes, one for each possible board position when it is Black's move. Each matchbox has pasted on it a drawing showing this board position, as well as all possible moves from that position, drawn in different colors. Inside each matchbox are several colored beads, one for each move on the top. When it is the machine's turn to move, the human operator finds the matchbox showing the current position, draws a bead at random from the matchbox, replaces it, and makes the move thus chosen. The machine learns from its losses: when it loses, the operator removes and discards the last bead drawn. This ensures that the machine will never lose in this way again.

To keep this on topic: this game could be implemented with a water computer, too. Replace the matchboxes with different colored buckets of water. Instead of removing a bead for a loss, dump out the corresponding bucket.

For a more enjoyable game, replace the buckets of water with shots of beer. =)

Re:I got to see the pics before they get /.ed

[kaiidth]

EMPs are basically just sudden extremely intense electromagnetic fields that appear and disappear, producing something like one nanosecond worth of electric field in whatever is within range. They're extremely 'dirty' - there's a large range of frequencies, which complicates things. The actual magnitude of the field isn't that great, less than your average lightning strike, but the problem is the rate at which the pulse occurs - which is much faster.

Any conductor will pick up on this effect, like metal pipes, land lines, what have you, which naturally tends to destroy anything connected to said devices. Processors and such are particularly vulnerable to, as you say, heating to destruction, since the devices cannot dissipate the extra heat.

You're pretty much right both ways, I think, in that overheating and 'messed up electrons' probably go hand in hand.

Incidentally, this hearing suggests another effect of high-altitude nuclear bursts, which is to fill the Van Allen belt with radiation and thus destroy all the low-earth orbit satellites not specifically designed for a high - radiation environment.