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New superconductor microprocessor yields a substantial boost in efficiency

spectrum.ieee.org

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Re: New superconductor microprocessor yields a substantial boost in efficiency

#211

Post by hoseja »

physicles wrote: post #183
faeyanpiraat wrote: post #129

Earlier quoted context omitted.

There is a Veritasium video really fun to watch which exmplains with examples why you cannot measure one way speed of light: https://www.youtube.com/watch?v=pTn6Ewhb27k

Yes! In uni I had this idea for a program that would triangulate where lightning struck by having multiple computers across campus listening for thunder, then measuring the difference in arrival times of the thunder. Like GPS in reverse. Soon I realized I’d need the computers’ clocks to be as in-sync as possible, which in turn requires one-way latency calculations. I spent an hour diagramming with pencil and paper un…

PTP/White rabbit.

Re: New superconductor microprocessor yields a substantial boost in efficiency

#212

Post by moosebear847 »

tsimionescu wrote: post #205
moosebear847 wrote: post #113

Earlier quoted context omitted.

In the future, I don't see why there's anything holding us back from splitting a bunch of atoms and having tons of cheap energy.

Nuclear fission has well-known drawbacks and risks that are fundemantal, they will never be engineered away (risk of catastrophic explosion, huge operating costs, risk of nuclear waste leakage, risk of nuclear weapon proliferation). Why do you think the future will be significantly different from the present in this regard?

These risks will most likely only reduce over time as our science and knowledge develops, barring a world-affecting mistake or war. If we can make a ton of energy, we can do many other things like launching the waste into outer space, and having a positive ROI by making more energy than it cost.

Re: New superconductor microprocessor yields a substantial boost in efficiency

#213

Post by chopin »

nicoburns wrote: post #168
AnIdiotOnTheNet wrote: post #43

Earlier quoted context omitted.

Considering that many modern interfaces are somehow less responsive than ones written over 20 years ago even when running those programs on period hardware , I feel certain that you are right.

Some things have improved a lot. Remember how long it took to boot a 2009 PC. I suspect if hardware perfromance stagnates then software optimisation will develop again.

I have a cheap Dell laptop from 2009 which boots in ca. 30 sec. A recent Linux Mint.

Compared to my recent company laptop which needs at least 2 min. Even more before I can work productively. For Windows 10.

It's definitely not dependent on hardware. Even not on functionality (I do the same on both machines).

Re: New superconductor microprocessor yields a substantial boost in efficiency

#214

Post by ginko »

the8472 wrote: post #18

> We use a logic primitive called the adiabatic quantum-flux-parametron (AQFP), which has a switching energy of 1.4 zJ per JJ when driven by a four-phase 5-GHz sinusoidal ac-clockat 4.2 K. The landauer limit at 4.2K is 4.019×10^-23 J (joules). So this is only a factor of 38x away from the landauer limit.

The interesting thing about this is that if we get close to the Landauer limit we may have to seriously start thinking of using reversible computing[1] paradigms and languages to get optimal performance.

[1] https://en.wikipedia.org/wiki/Reversible_computing

Re: New superconductor microprocessor yields a substantial boost in efficiency

#215

Post by nicoburns »

chopin wrote: post #213
nicoburns wrote: post #168

Earlier quoted context omitted.

Some things have improved a lot. Remember how long it took to boot a 2009 PC. I suspect if hardware perfromance stagnates then software optimisation will develop again.

I have a cheap Dell laptop from 2009 which boots in ca. 30 sec. A recent Linux Mint. Compared to my recent company laptop which needs at least 2 min. Even more before I can work productively. For Windows 10. It's definitely not dependent on hardware. Even not on functionality (I do the same on both machines).

Swap your OS's and you'll still notice an improvement in the hardware. Windows has always been slow. SSDs have made even windows fast to boot on every recent laptop I've used though.

Re: New superconductor microprocessor yields a substantial boost in efficiency

#216

Post by ubitaco »

qayxc wrote: post #175
faeyanpiraat wrote: post #130

Earlier quoted context omitted.

I'm no physicist, but wouldn't you need some kind of medium to efficiently transfer the heat away? On the moon you have no atmosphere to do it with radiators with fans, so I gues you would have to make huge radiators which simply emit the heat away as infrared radiation?

> On the moon you have no atmosphere to do it with radiators with fans, so I gues you would have to make huge radiators which simply emit the heat away as infrared radiation? Exactly. You can still transport the heat efficiently away from the computer using heat exchangers with some medium, but in the end radiators with a large enough surface area will be required. Works well enough on the ISS, so I imagine it'd work…

I'm also not a physicist, but for the fun of the discussion...

Radiative heat loss scales with the fourth power of temperature. I don't know what temperature the ISS radiators are but suppose they are around 300K. Then I think the radiative surface to keep something cool at 10K would need to be 30^4, or 810000 times larger per unit heat loss. So realistically I think you would need some kind of wacky very low temperature refrigeration to raise the temperature at the radiator, and then maybe radiate the heat into the lunar surface.

Re: New superconductor microprocessor yields a substantial boost in efficiency

#217

Post by ygra »

m3kw9 wrote: post #191
yazaddaruvala wrote: post #118

Earlier quoted context omitted.

For anyone too lazy to math, its a car that can go: 28.4 million km per hour (i.e. 17.6 million miles per hour) I wonder how much that speeding ticket would cost. Disclaimer: Assuming the one-way speed of light is 300k km/s

The sonic boom would destroy anything in a few mile radius

The heated plasma from compressing the atmosphere as well. I guess the progression of events and the carthage is similar to the relativistic baseball.

Re: New superconductor microprocessor yields a substantial boost in efficiency

#219

Post by jlokier »

patagurbon wrote: post #119
aqme28 wrote: post #97

Earlier quoted context omitted.

I was curious about this too. This chip is using adiabatic computing, which means your computations are reversible and therefore don't necessarily generate heat. I'm having trouble interpreting what exactly that means though.

But you have to save lots of undesirable info in order to maintain the reversibility right? Once you delete that don't you lose the efficiency gains?

You don't need to delete the extra info.

After reading the output, you run the entire computation backwards (it's reversible after all) until the only state in the system is the original input and initial state.

Then you can change the input to do another calculation.

If implemented "perfectly", heat is produced when changing the input and to read the output.

Reading the output will disturb it so the computation won't perfectly reverse in practice, however if the disturbance is small, most of the energy temporarily held in circuit is supposed to bounce back to the initial state, which can then be reset properly at an appropriately small cost.

Quantum computation is very similar to all of this. It too is reversible, and costs energy to set inputs, read outputs and clear accumulated noise/errors. The connection between reversible computation and quantum computation is quite deep.

Re: New superconductor microprocessor yields a substantial boost in efficiency

#220

Post by MrYellowP »

ygra wrote: post #217
m3kw9 wrote: post #191

Earlier quoted context omitted.

The sonic boom would destroy anything in a few mile radius

The heated plasma from compressing the atmosphere as well. I guess the progression of events and the carthage is similar to the relativistic baseball.

Relevant xkcd: "What would happen if you tried to hit a baseball pitched at 90% the speed of light?"

https://what-if.xkcd.com/1/

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