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Research paper: https://arxiv.org/abs/2307.12008
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this post was submitted on 26 Jul 2023
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Does this get us hovering without rails? Could we theoretically generate a magnetic field strong enough to repulse the earth? Or is that still Science Fiction?
You still need a magnet-superconductor pair for quantum locking and magnetic levitation. This is called the Meissner effect and it seems like it has been confirmed for this material. Here’s a video showing an example of such a system.
Before, the best way to scale this up might’ve been to make permanent magnet rails and run a superconductor train along those rails, but that would have been totally infeasible and inapplicable in real life, since building rails out of permanent magnets is expensive and dangerous, and the train would need to house a really large superconductor chilled to liquid nitrogen temperatures. You couldn’t have built a track out of superconductors irl because good luck keeping those at the temperatures required for superconductivity to kick in.
If this material turns out to actually work as claimed and to be producible at scale, you can switch those and make an electromagnetic train that travels along superconductor tracks. Which is way easier, cheaper and much more doable in general.
But the earth’s magnetic field is extremely weak, and even the tiniest pieces of superconductors are unable to lock with it. So no, it does not allow for trackless levitation.
But a cool new train system design becomes possible though!
Superconducter maglevs are feasible and have been in service for years. They are building a large line in Japan.
You're right, haven't heard about that one. They actually do use superconducting magnets on a train that runs along a magnetic track.
But I feel like my feasibility comment still stands. It seems like all they had built is a 18km test track, and there's some info about extending it to 48 km, but it doesn't seem like the extended part uses superconducting tech yet, it only mentions regular maglev. The Tokyo — Osaka line is planned for 2037. So yeah, its technically possible, but it's not like you can cover Europe or the US with this type of track for any sensible amount of money.
That's the cool part about room temperature superconductors, they make this type of tech possible on much larger scales.
It sounds like the full line will eventually go across most of Japan and operate in the same way as the test track, however it is expected to be very expensive, and room temperature superconductors would likely lower the cost.
I've seen that video so many times, but it never stops looking fake.
Superconducting materials will expel an induced magnetic field as it creates internal fields that exactly cancel out the induced one. You'd still need some sort of "rails" to created the induced field and to move it to generate forward motion.
That is for the Meissner effect I think. I guess what I was thinking is to use the SC to create an incrediblely strong electromagnet to repel the Earth's magnetic field. But it looks like we are orders of magnitude away from that
The earth's magnetic field is so weak that you'd be repelling something the mass of a compass needle.