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Superconducting Microprocessors? Turns Out They're Ultra-Efficient (2021)

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Re: Superconducting Microprocessors? Turns Out They're Ultra-Efficient (2021)

#31

Post by oceanplexian »

philipswood wrote: post #25
incompatible wrote: post #13

: The research group in Japan sought to create a superconductor microprocessor that’s adiabatic, meaning that, in principle, energy is not gained or lost from the system during the computing process. I thought that there was a law of information theory that requires expending energy, I think it's Landauer's principle. It seems to be disputed though. https://en.wikipedia.org/wiki/Landauer%27s_principle

Energy is expended when you zero or set a bit. If you compute reversibly you need use special logic gates to not throw any bits away during the computation, like the Toffoli gate. All your operations need to have the same number of input and output bits and needs to be able to run forwards and backwards. Effectively you set or zero no bits during the entire computation that can't be losslessly reversed. If you struct…

My analogy probably isn’t perfect but isn’t this how an abacus or a slide rule works? You expend energy to set the values for computation but the act of computing and then reading them expends no energy.

Re: Superconducting Microprocessors? Turns Out They're Ultra-Efficient (2021)

#32

Post by jasonwatkinspdx »

wizardforhire wrote: post #2

Another notch on the belt for a cryocooler boom. Oh “superconducting is hard”, “if only we had high temperature superconductors”. All valid, but if we work with what we got and disrupt cyrocoolers make them a commodity like magnetrons all those laments become moot. Prove me wrong.

I'm fond of this argument but I would point out that magnetrons are remarkably simple devices once you figure out how the waves are interacting.

Re: Superconducting Microprocessors? Turns Out They're Ultra-Efficient (2021)

#34

Post by AnthonyMouse »

philipswood wrote: post #25
incompatible wrote: post #13

: The research group in Japan sought to create a superconductor microprocessor that’s adiabatic, meaning that, in principle, energy is not gained or lost from the system during the computing process. I thought that there was a law of information theory that requires expending energy, I think it's Landauer's principle. It seems to be disputed though. https://en.wikipedia.org/wiki/Landauer%27s_principle

Energy is expended when you zero or set a bit. If you compute reversibly you need use special logic gates to not throw any bits away during the computation, like the Toffoli gate. All your operations need to have the same number of input and output bits and needs to be able to run forwards and backwards. Effectively you set or zero no bits during the entire computation that can't be losslessly reversed. If you struct…

Wait, so does this imply (ignoring the time requirements) that you could do NP calculations with a feasible amount of energy, because the inputs and outputs are small?

Combine that with something that uses time dilation to make it go fast (from our frame of reference) and you'd be giving even hypothetical quantum computers a silver medal.

Re: Superconducting Microprocessors? Turns Out They're Ultra-Efficient (2021)

#36

Post by BenoitP »

This is the future. As we try to go 3D and start stacking dies, the limiting factor of heat is getting even more blocking.

It's not about consuming less electricity. It's about dissipating less of it as heat inside the microprocessor. The future will made of tiny porous cubes that are tall sandwiches of RAM and CPU/GPU/etc

Re: Superconducting Microprocessors? Turns Out They're Ultra-Efficient (2021)

#38

Post by sigmoid10 »

BenoitP wrote: post #36

This is the future. As we try to go 3D and start stacking dies, the limiting factor of heat is getting even more blocking. It's not about consuming less electricity. It's about dissipating less of it as heat inside the microprocessor. The future will made of tiny porous cubes that are tall sandwiches of RAM and CPU/GPU/etc

Superconductivity with current materials is hard. Allost always because of the cooling. You can't just fabricate a porous cube of transistors and put it in a liquid helium ice bath. You need to have excess heat flowing out in a stable and predictable way. Otherwise once the center reaches critical temperature, the whole thing will explode. There's a reason why everyone is desperately searching for room temp low pressure sc materials. I doubt we'll see industry applications in large scale computing before that.

Re: Superconducting Microprocessors? Turns Out They're Ultra-Efficient (2021)

#39

Post by Dylan16807 »

AnthonyMouse wrote: post #34
philipswood wrote: post #25

Earlier quoted context omitted.

Energy is expended when you zero or set a bit. If you compute reversibly you need use special logic gates to not throw any bits away during the computation, like the Toffoli gate. All your operations need to have the same number of input and output bits and needs to be able to run forwards and backwards. Effectively you set or zero no bits during the entire computation that can't be losslessly reversed. If you struct…

Wait, so does this imply (ignoring the time requirements) that you could do NP calculations with a feasible amount of energy , because the inputs and outputs are small? Combine that with something that uses time dilation to make it go fast (from our frame of reference) and you'd be giving even hypothetical quantum computers a silver medal.

If you're going to use time dilation so you can wait for the computer to calculate, it's hard to imagine a setup where the power needs of the computer are more than a rounding error in comparison.

Re: Superconducting Microprocessors? Turns Out They're Ultra-Efficient (2021)

#40

Post by HPsquared »

KiranRao0 wrote: post #15
incompatible wrote: post #13

: The research group in Japan sought to create a superconductor microprocessor that’s adiabatic, meaning that, in principle, energy is not gained or lost from the system during the computing process. I thought that there was a law of information theory that requires expending energy, I think it's Landauer's principle. It seems to be disputed though. https://en.wikipedia.org/wiki/Landauer%27s_principle

Per the wikipedia article: “Modern computers use about a billion times as much energy per operation.” I’m guessing the efficiency gains can be considerable before hitting this limit.

That's actually fewer zeroes than I was expecting.
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