Everyone seems to be excited about using Diamagnetic Repulsion to levitate stuff (frogs most recently) but it occurs to me that the best use of this technology is not to counter gravity but to simulate it.
Mount these Repulsors in your space station wherever you want "up" to be. If I understand the theory, it acts on all molecules simultaneously, so your body would be unable to tell the difference between Magnetic repulsion from "up" and gravitic attraction from "down". Muscle degradation, odd bone growth, and the constant threat of nausea would be eliminated. You could even design your ship to use maximum surface area by making each corridor have its own "gravity"...
I would really like to hear from someone who understands this theory to tell me why I am wrong about this (I assume there is some flaw in this theory)-- dbsousa, Jan 17 2003 (?) Levitating Frog http://www-hfml.sci.kun.nl/levitate.html [Shz, Oct 04 2004, last modified Oct 21 2004] Surgery in Space http://www.space.ed...jensen/bernier.htmlYou may ask yourself... [dbsousa, Oct 04 2004, last modified Oct 21 2004] "National Radiological Protection Board" recommended limits for exposure to magnetic fields. http://star-www.st-...afety/magnetic.html2 tesla for short periods, 1mT long-term. [Monkfish, Oct 04 2004, last modified Oct 21 2004] Be sure and not wear anything made of metal.-- RayfordSteele, Jan 17 2003 Any metal, or normally magnetic metal?-- dbsousa, Jan 17 2003 Diamagnetic what? Link please.-- egbert, Jan 17 2003 //I think you'll need to approach 1 gravity (think power consumption!) with this thingy, for any palpable effect. (on muscle loss, etc.)//
Really? I was under the impression that we haven't determined the threshhold of gravity that will prevent these.
Even if it requires 1G, you might not need it all the time. an hour a day in 1G might be enough to prevent atrophy. And as far as power is concerned you might keep it localised to a small chamber. It may be the only way to perform operations in space, for example...-- dbsousa, Jan 17 2003 The advantage of diamagnetic levitation seems to be that it works with permanent magnets; it needn't require ongoing energy input. (Perhaps a little to keep a superconductor cool, etc.)
One interesting thing about this scheme is that some things would float and some wouldn't.-- Monkfish, Jan 17 2003 Doesn't it sound like the magnetic field would have to be too strong to do anything in? How strong is 16 Tesla? (For the frog.)
And would different people need different magnetic field strengths? Don Zimmer has a metal plate in his head but I only have a few fillings in my teeth.-- crawdaddy, Jan 17 2003 Strong magnetic fields seem to be a potential health risk (see link). They don't sound immediately lethal or anything, but it also sounds like not much is known about their effects. There may be more important problems, of course.
It would be interesting to be able to rotate your magnets around the station to change the direction of "down" as needed. (Beds on the ceiling, and all that.)-- Monkfish, Jan 17 2003 Wouldn't it be easier to just spin the whole thing?-- Crazy Bastard, Jan 17 2003 You could power the device with a solar panel... the size of Texas.-- X2Entendre, Jan 17 2003 By the way, 4 tesla can make you dizzy-- qaza, Jan 17 2004 assuming this would work, it would need to be shielded, as it would probably wreak havoc on all the electronic equipment.-- theircompetitor, Jan 17 2004 Aside from the possible health risks, magnetic fields drop off as an inverse of the distance from the source, meaning that unless you had an absolutely colossal magnetic source positioned at a large distance from the intended subject, you'd feel much more downward pressure on your head than you would on your feet.
Gravity is assumed constant for most purposes on earth because the associated scales are so small (5 or 6 feet, or even a few thousand feet) when compared to the radius of the Earth. When dealing with large distances (orbital altitudes, for example) variations in gravity due to distance have to be factored in.
Even generating artificial gravity by spinning the station is only truly useful on large-scale structures due to the discernable difference in force when the rotational radius is not orders of magnitude larger than the subject.-- Freefall, Jan 26 2004 Well, it certainly makes more sense than "Gravity Just May Be Electric Force."-- spacecadet, Jan 26 2004 <natural law>If a conductor (for example, human brain tissue) passes through a magnetic field, a current will be induced in the conductor.</natural law>
I dunno if I want to do that, even if the current induced is small and sporadic...-- galukalock, Jan 26 2004 Halfbakers: vote for or against, but do not miss that levitating frog link. Thank you Shz for that. There is video! (big files, need a fast connection)-- gardnertoo, Jul 28 2004 random, halfbakery