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Scientists Levitate Mice (msn.com)
66 points by brandnewly on Sept 10, 2009 | hide | past | favorite | 33 comments



I wonder how much money and power it would take to build a human sized magnetic levitation chamber...


I would be more interested to get in the Hoverboard business with this kind of technology.


It seems like this hoverboard, though, would work best over water.


I wonder if there is enough water in the air under a potential hoverboard or in soil, roads, etc?

I guess hovering over water, snow and ice would still be cool.


First you have to think for a braking system for the hoverboards.


Thats easy: turn off the hovering!


The wise man avoids the face-brake. :)


According to the original paper, they needed a 17 Tesla magnet to lift a 10 g mouse. I'm not exactly sure how to extrapolate that, but if it's linear it seems like you would need on the order of 100 kiloTelsa to lift a 150 lb person.


And 100 kilotesla is much greater than the largest magnet ever created -- the cost of building a magnet of increasing strength increases exponentially. The most powerful continuous magnetic field is 45T and the lab has 300 employees.

http://en.wikipedia.org/wiki/Orders_of_magnitude_(magnetic_f... http://blog.tlb.org/superpowers-0


I'm quite sure it's not linear by weight supported.

The field exists in the entire area, each water molecule gets supported individually by the field. So the field needs to be strong enough to lift a single water molecule against earths gravity. (Plus some extra since water is also lifting misc other stuff in the body.)

You don't need a stronger field, you need one that covers the entire area, at the original strength. To do that you do need it somewhat stronger due to the dropoff by distance from the magnet.

But you don't need it stronger to support the weight.


Magnetic fields drop off as the cube of the distance, because the molecules further away will experience much less force you will need a much larger magnet anyway.

That's not 'somewhat' stronger, that's a lot stronger.

If a mouse is 25 mm high and you would want to levitate something the size of a human of say 1.75 m high with the same density as a mouse then the required magnet would have to be roughly (8^6)/2 times as strong for the same effect.

Then you still have to take into account the size difference at the base of the field, figure another factor of about 10 or so for that.

If you take the 'easier' approach and levitate a person while laying down (probably a wise thing) then the required magnet strength would be smaller, but still not that much smaller, you now have a vastly large surface area to work with ~40 times as large, (30,000 square cm opposed to 75 square cm), and the height is still 10 times as much so figure another 8^3 as much for that.


a levitation chamber wont be that much fun. I think a tool which you can wear or maybe shoes which can replicate the magnetic field, will be more relevant. A chamber will be equivalent to a gravity-free chamber, which, already exists.


But gravity-free chambers are dependent on fast downward drops and so are limited by time. A magnetic one you could float around in for as long as you were prepared to keep paying for the electricity.

Another voice here for the startup idea...to be frank, you could probably make the money back just from people who wanted to have zero-g sex.


Should be very difficult. (The sex, and getting enough resources to generate a human-hovering magnet field.)


I'd certainly pay for the privilege! Go DannoHung, startup awaiting :)


Wouldn't this cause some trouble on humans? If I understand how this works correctly, unless they have a completely empty stomach or levitate in a horizontal position there could be some unwanted levitation of fluids taking place..


This reminds me of a Mythbusters episode I saw where they tried numerous "antigravity" devices. A few of them did manage to levitate objects, but worked either on magnetic fields or thrust. There was no alteration of gravity.

That said, I'm a bit confused as to how scientists want to apply this achievement to low-gravity environments. Since gravity is not actually being altered here, it doesn't seem relevant. Am i totally off base here?


"Gravity" isn't being created, but a uniform force is being applied at the molecular level, which is effectively the same. It is currently being applied "up" at roughly the same force as gravity, causing levitation. Vectoring this force down instead of up will produce force indistinguishable from gravity.


Clearly there are differences, but many of the same conditions apply, such as low pressure on the bones, so that it can still be useful in /most/ studies related to microgravity. It's a little like using an animal to test medicine -- there are differences, but the initial work can often be completed because of the overwhelming similarities.


""It actually kicked around and started to spin, and without friction, it could spin faster and faster, and we think that made it even more disoriented," said researcher Yuanming Liu, a physicist at the Jet Propulsion Laboratory in Pasadena, Calif. They decided to mildly sedate the next mouse they levitated, which seemed content with floating. "

That mouse got high in more ways than one.


"Then it proceeded to travel North"

I totally made that up.


I'm totally calling PETA.


Here's a levitating frog:

http://www.youtube.com/watch?v=A1vyB-O5i6E

1997, as Confusion mentions.


I wonder if they can somehow modify this to create artificial gravity. Anybody here who knows something about this subject?


Flip the levitating device upside down and put it above the mouse? That would be my guess :)


Diamagnetism only repels, it doesn't attract. All materials are diamagnetic.

Ferromagnetism does both, attracts and repels, but only certain materials are ferromagnetic.

It's not gravity BTW, it's magnetism.


Thanks. I'm going to read up on that :-)


The first living creature to be levitated was a frog, in 1997: http://www.hfml.ru.nl/froglev.html. This link is completely devoid of news.


"Other researchers have made live frogs and grasshoppers float in midair before, but such research with mice, being closer biologically to humans, could help in studies to counteract bone loss due to reduced gravity over long spans of time, as might be expected in deep space missions or on the surfaces of other planets."


If you can levitate a frog, then you can levitate a mouse. Nothing new in that. Research on mice yields better predictions as to what would happen to humans. Nothing new in that.


6 years until hoverboards are mainstream.. I'd say we're right on target.


Have you seen Steve Jobs? I'm pretty sure he can levitate. :)


All science aside, I actually laughed out loud at this one.

If there's anything funnier than a small floating mouse spinning out of control, I can't think of it.




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