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After the WorldBuilding community helped Average Joe start his own microstate, Joe has become scientifically inclined, and uses his money to conduct somewhat dangerous research projects from his new soverign position as President of Somewhere. (Might not end well)


Now Joe, thinking he can do everything, has decided to invest money in antigravity research. His top scientists tell him that magnets are the way to go: if we can make a frog fly around in a magnetic tube because water is diamagnetic, why not try the same with people, another fairly water-rich species?


Assume:

  • Joe has the money to build an electromagnet as large as he wants, or research until he can achieve extreme magnetic attraction
  • It is set up the same way as in the classic frog experiment, just on a larger scale
  • Joe is Average (there is no special weight, composition etc within Joe)
  • Real physics must apply. No unobtanium, magic, law bending, etc.
  • Joe's scientists don't have to be right about magnetic levitation being cost-effective or "The way to go". This question is not asking for realistic levitation, it's asking what powerful magnets can do to the body.

Prompt

  • Frogs were used in the original experiment because they are made up of a significant amount of water, and it's spread pretty evenly. Humans have a less even distribution of water; will that mean areas such as the stomach, digestive track, skull etc are at risk of being pulled outward? (This is not specifically what I'm answering, just something to consider in an answer)
  • Blood contains a whole lotta iron

Before Joe hops inside the electromagnet, he needs to know:

  • What are the health risks of a small amount of magnetism - just enough to hover a few inches?
  • At what point does Joe need to take measures to protect himself?
  • How much magnetism will kill Joe?
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  • $\begingroup$ he really want to levitate like the frog, or magnetic field affecting his suit, or boots with magnets in them and magnetic floor (hover board boots) are fine for him. $\endgroup$ – MolbOrg Nov 15 '16 at 3:18
  • $\begingroup$ I say rehearsal visits the docs for daily MRI scans or even better see a psychiatrist even after you manage to clear all tests... $\endgroup$ – user6760 Nov 15 '16 at 6:31
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    $\begingroup$ A frog's percent water content isn't significantly different than that of a human. Magnetic levitation has been performed on creatures as different as a grasshopper and a mouse. The size difference could matter, though. Also, the iron in blood is not in its metallic state and is not affected by magnets. X-Men lied to us. (Except that you can levitate a person with a strong enough magnetic field, but it's because of the water, not the iron.) $\endgroup$ – IndigoFenix Nov 15 '16 at 6:45
  • $\begingroup$ @IndigoFenix Isn't water more concentrated in a human in certain areas even if the percent is about the same? $\endgroup$ – Zxyrra Nov 15 '16 at 12:43
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Although I was unable to find a conclusive answer to this exact question (despite the number of times it has been asked), I would presume that a person can be levitated safely.

Magnetic levitation of living organisms works through diamagnetism, which is basically the water in your body "pushing" against the magnetic field. Living organisms can be levitated because their bodies are mostly water, and that water is pretty evenly distributed throughout the body, since every individual cell is basically a tiny bag of water with some stuff mixed in. This is the case regardless of whether the organism is a frog, a grasshopper, a mouse, or a human. The force applied to every water molecule is equal, meaning that you would be effectively weightless while suspended in the field.

The only part of the body that is made up mostly of something other than watery cells are the bones, and that isn't going to be a problem, since the meat of the body is perfectly capable of supporting the bones against gravity. Otherwise your skeleton would fall out.

While a strong enough magnetic field (such as one produced by a magnetar, a kind of neutron star) is capable of ripping you apart atom by atom, this force will naturally be much, much higher than the amount you need to simply levitate.

You will need to make sure to have adequate radiation shielding on whatever is producing the magnetic field though. Anything capable of producing a magnetic field strong enough to levitate a person will generate a ton of radiation when it is turned on, which can fry your brain if you aren't protected. Switching the field on and off quickly while inside it can also mess with your brain, but as long as it stays on it shouldn't cause any issues.

Also worth noting: keep any magnetic metal objects far, far away when performing the experiment. A magnet that powerful will attract metal from quite a significant distance, and being skewered by flying lab equipment when you're trying to levitate would not be fun.

The iron in your blood is not in a ferromagnetic state and magnets have no particular effect on it, so don't worry about that.

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  • $\begingroup$ This answer is helpful, and it will probably be the one I choose, but could you please identify how areas with higher-than-average water concentrations will react? While every cell does contain water, certain organs or organ systems have it much more abundantly (stomach, bladder, intestines etc) $\endgroup$ – Zxyrra Nov 16 '16 at 3:21
  • $\begingroup$ @Zxyrra It shouldn't matter - the strain on any given organ should be less than that which it experiences in everyday life. The ground holds your entire body up against gravity, even though it is really only "holding you up" by the bottom of your feet. This is even easier - you are being "held up" by the water in every single cell. The water in some organs might float around a bit, which might make you feel a bit queasy if you did it for too long, but that's no different than what you'd feel in weightlessness. Ultimately, the force exerted on any body part is only 1 G. $\endgroup$ – IndigoFenix Nov 16 '16 at 9:45
  • $\begingroup$ Nice answer, but what radiation exactly? It's a magnet. I'd worry about eddy currents if the person tries to move (even a breath or a heartbeat(!), not that I have citations on how bad that might be) but not radiation. $\endgroup$ – BenRW Jan 11 '17 at 18:25
  • $\begingroup$ @BenRW The magnetic field won't produce radiation, but you're not going to get a field this strong from anything short of a very powerful electromagnet, and that will produce radiation when it is first turned on due to the change in electric current. $\endgroup$ – IndigoFenix Jan 12 '17 at 6:53
  • $\begingroup$ @IndigoFenix Wouldn't that be exactly the same change as one would get from entering the electromagnet after it's been switched on? $\endgroup$ – BenRW Jan 12 '17 at 12:17
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First, we need to examine our Average Joe.

The highest human exposure I can find is an 8 Tesla field--it causes no harm to a person. However, fields like that can easily kill if you have ferrous bits in your body (the most common cause being an undetected pacemaker) or even due to nearby ferrous objects.

As to the energy, the best I'm finding is levitating a frog with a 16T field. A human will obviously require a vastly stronger field.

Thus I'm forced to conclude that whether this is safe or not is outside the realm that has been studied.

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    $\begingroup$ While I acknowledge that parts of this are outside the realm of that which has been studied, so too is half of this site - and yet answers seem to work on here. I wouldn't call this "unanswerable" $\endgroup$ – Zxyrra Nov 15 '16 at 1:52
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    $\begingroup$ If I had an undetected pacemaker, I would be seriously reconsidering my life choices... $\endgroup$ – Frostfyre Nov 15 '16 at 13:18
  • $\begingroup$ @Frostfyre The undetected pacemakers are in the ER. $\endgroup$ – Loren Pechtel Nov 16 '16 at 5:20

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