[mitthrowaway2]

Superconductors change every assumption about how we harness electricity and magnetism. Beyond reducing the cost of electricity transmission, they enable all sorts of fascinating applications:

- They enable low cost, continuous, passively-stable magnetic levitation. Superconductors could replace ball bearings in many applications.

- They enable permanent magnets that are far stronger than any we make from conventional magnetic materials. For example, motors tend to run at high speed and low torque, so as to minimize heat generated from current in the copper windings. Superconducting direct-drive motors could allow for ultra-high-torque actuators without any need for gearing, and with minimal heat generation or losses. So superconducting electromagnets could replace everything from electric motors to hydraulic pistons to simple springs.

- Superconductors allow for very sensitive antennas and magnetic field sensors, allowing for near-field detection of very small signals (such as from neurons firing in the brain). There is a lot of impressive technology that only exists inside research labs where a generous supply of cryogenic liquids are always on hand. Those could make their way into mass-market products.

That's just a very short list.

[LinAGKar]

Something that immediately comes to mind for me in Sweden, is that the country is fairly long in latitude, and most of our electricity production is from hydroelectric power in the northern half of the country, while most of the population is in the southern half of the country. Better energy transmission could help a lot.

[postmortembees]

What if your PC did not need cooling, because it generated no heat? How much more potent could computers be?

[mitthrowaway2]

It probably wouldn't greatly affect the heat generation in a PC, unless the transistors could themselves be replaced with some superconducting alternative. Harnessing the efficiency from that would probably require that the computer be designed as a reversible computer. It would be its own research avenue.

[sudosysgen]

Unfortunately, as soon as you actually use the result of the computation in any kind of practical manner as an output, you break reversibility, though you could make the heat production happen away from the computation.

[marcosdumay]

The idea of reversible computing is that if you only add heat in a few instructions, you can have a much more economical computer. And magnetronics is a good candidate for implementing this, so yeah, computers that use a lot less power are an application too.

[sudosysgen]

I haven't seen any reversible low power superconducting gate that can credibly operate at a high temperature - not because of the superconductor itself, but because of thermal noise. Again, I haven't read through the literature in this field for a while (and it wasn't that extensive either), but from what I recall what you're proposing is roughly as difficult as making a gate for a quantum computer, and you have to keep your system way colder than your critical temperature from that due to thermal noise. If you have any links for high temperature physically reversible logic gates I'm all ears.

[MayeulC]

I don't think you actually need reversibility if you don't discard the energy but return it to the power supply?

In other words, "reversibility", but you can actually pool the useless results together, you don't need to separate them later. Or so I read somewhere...

[sudosysgen]

I might be wrong since I've studied this a long time ago, but from what I remember, in order to do that classically, you need to copy the output bits somewhere else before uncomputing your system and recovering the ancilia.

That's technically fine, as long as you have an infinite supply of stably initialized bits onto which to copy your result. Initializing those bits is going to be non-reversible in some way.

[piyh]

Pentium 4 to 10 GHz, here we come!

[sudosysgen]

Computation inherently generates heat, but if you could make chips that release negligible amounts of heat, you would unlock the third dimension which would help with reducing signal length and enable computers to be significantly faster.

[tills13]

That this as a solution applicable to _personal_ computing is a bonus. The real benefit is in datacenters which could be made smaller, more efficient, and cheaper while simultaneously adding capacity.