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[Zanzetkuken The Great]

Would a superconductor acting with the Meissner effect, if attached to the magnet suspending it and a contained environment that could be attached to something, be able to be utilized to stabilize and excessively large skyscraper or a flying city?

[Sergarr]

You'd still need to prop the magnet on something.

[Zanzetkuken The Great]

You'd still need to prop the magnet on something.

So it wouldn't work as such:

    [-=-]
<---[   ]--->
    [---]

The bottom row being the magnet, equals being the superconductor being suspended by the magnet, and the two arrows representing attachment points.

[i2amroy]

That would hypothetically work, but you're looking at a whole host of engineering problems. I'll do my best to list some of them:
1) The force on the supports would be immense. There's a reason we build our buildings like this:
(C = container for the building)

Code: [Select]

C
-
|
|
|
-Instead of this

Code: [Select]

|---C---|
|       |
-       -A horizontal beam provides zero support to a vertical thing it is attached to (other than it's own intrinsic ability to resist bending, which is factors of magnitude lower than it's ability to resist compression). You could compensate somewhat by using something like carbon nanotube ropes to hold it up, but even then it would look more like this:

Code: [Select]

|-_   _-|
|  -C-  |
-       -
2) Your building flipping over. Most of our buildings are guaranteed to not flip over randomly, so the center of gravity can be pretty far up on the building. A floating building doesn't really have near as much of a guarantee, so you'd need to address the problem. Probably the best way to do that is just to have a freely rotating shell that your actual building was in, so that the building was always guaranteed to remain upright.

3) The strength of a magnet you would need. While this isn't a problem in the "house" range, once you start to get into the "skyscraper" type of range you end up with a field that is strong enough that anyone moving through the field would experience nausea and disorientation. This wouldn't be a problem inside of the shell around your floating building, but anyone moving to/from the building would be in for a bad time. It would also be strong enough (even in the house range) to start messing with things like pacemakers and pull slightly on anything ferromagnetic (iron/steel for the most part).

4) Assuming you used a shell to stop your building from flipping, you run into all sorts of problems with getting through the shell. Doable, but a pain in the ass for the designing engineers.

5) Getting up/down from your floating building.

5) Horizontal forces. Without anything to tether it in place, even simple things like stepping from whatever method you use to get up to it into your floating building would exert a horizontal force that would cause it to start drifting over time. Anything like a tiny wind would make it go flying like an ice skater. It's very likely your floating building would end up drifting to rest up against the side of the container pretty quickly without constant corrections.

So yes, it's possible, but you're looking so far outside of the realm of plausible that you aren't going to see it happening. For the amount of problems it would cause you'd be better off just building a normal skyscraper up to whatever height you were originally going to suspend your floating building inside a shell inside a container at, and then building whatever building you wanted to float on the top. It would cost less, be more feasible to build, and would have greater floor space by the factor of a couple of magnitudes.

[Zanzetkuken The Great]

-snip-

1) Was mainly using the arrows to represent where attachment points could be.  I wasn't trying to say it would wind up being implemented that way.

2) Would dropping the device in a gyroscope work?

3) Alternatively, use multiple smaller ones rather than one big one.  Could also provide redundancy.

Second 5) I was wondering if it would keep going or not.  In the case that it does, why not use smaller ones to assist in launches?  Or aiding in the buoyancy of more impractical boat designs.

Final bit: I had mentioned either assisting in stabilizing skyscrapers in the first post, with the other being a full-out flying city.

[i2amroy]

1) Really the best thing is just to mount the magnet on the ground.
2) That's basically the idea. The flipping problem is more at the building level than the container one though, so you'd need to ensure that no matter what the building's center of gravity is always on the bottom half (with lower spots corresponding to less tilting in the presence of horizontal forces).
3) Multiple smaller ones would work, but really as I noted we're running the point where it's more feasible just to build a conventional city and then use the extra money and resources to make living there free and encase the whole thing in a climate controlled dome.
5) It won't technically "keep going", since there is always air friction, but yeah, when it's floating it's essentially on a near friction-less surface.

One thing I apparently forgot to calculate in in my first calculations is that magnetic field strength drops off with the cube of the distance. Superconductor levitation distances are usually measured in mm. A rough back-of-the-envelope calculation with that factored in kinda makes my other points obsolete, since if you want an outhouse floating 20 or 30 feet up in the air you're gonna be dealing with magnetic fields so strong that it would cause severe nausea and disorientation in anyone trying to move in it. It would be strong enough that if a smaller animal ran onto your magnet you could hypothetically levitate the animal due to the water content in it's body!