Avatar's floating boulders

[Fanghur]

Does anyone know whether or not the levitating boulders on Pandora is realistic? I mean I know that at the very least the science behind it is sound; superconducting material levitating in the presence of strong electromagnetic fields is a well known phenomenon called the Meissner effect. So since "Unobtainium" is both a room-temperature superconductor and gives off strong magnetic fields, theoretically it would levitate; but could the Meissner effect really cause whole boulders to levitate like that?

[Cap'n Refsmmat]

In the presence of a sufficiently large disbelief suspension field, I suppose it can.

[JoeOh]

Even with a room-temperature SC it would have to be immersed in one HELL of a dense magnetic field area.

[Sisyphus]

superconducting material levitating in the presence of strong electromagnetic fields is a well known phenomenon called the Meissner effect.

 

Sort of. The Meissner effect is the phenomenon of superconductors being perfectly diamagnetic, i.e. that they repel and are repelled by magnetic fields to the point where there can be no magnetic field inside them. This can be taken advantage of to suspend them in air (at the point where the local field is weakest, for example), but levitation is not the direct result.

 

So since "Unobtainium" is both a room-temperature superconductor and gives off strong magnetic fields,

 

I don't know how this would work. Are they electromagnets? I don't think a superconductor can just "give off" magnetic fields without some kind of current.

 

but could the Meissner effect really cause whole boulders to levitate like that?

 

Whole boulders could be levitated in a strong enough external field, sure.

 

Caveat: I haven't even seen this movie.

[Severian]

While I think it is probably possible in principle, the sheer scale of the thing is probably unreasonable. The magnetic fields would need to be enormous - so much so that I think a human being couldn't survive near them, and electronic equipment certainly wouldn't.

 

So as it is depicted in the movie is, I think, not possible.

[StrontiDog]

You're all forgetting that Unobtanium, when it decays, produces two main daughter products called Impossibilium and Thatsjustsillium. Obviously, the rocks are composed mostly of these two substances.

 

Another key factor in the science behind the movie is that the floating rocks are all anchored by those huge vines, which are of the genus/species Looksgoodicus onnascreenium.

 

And the Suspension of Disbelief Field was created and maintained by the POA* Effect. Pretty obvious, really.

 

How can you folks call yourselves scientists? Sheesh!

 

Bill Wolfe

 

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