Controlling magnetism with superconductors

I remember reading Dick Tracy as a kid. They had these vehicles that apparently had a magnetic field that opposed the earth's field, as I recall.

If you place two magnets side by side, say north poles to the left and south poles to the right, there will be a force pushing them apart. The closer they are, the stronger the combined field and the more energy stored in it.

The repulsive force is the change of energy with respect to displacement,

F = dE/dx.

This force is significant for small strong magnets close to each other, where the field strength drops off rapidly with distance. The field of the earth is so large that the change in field strength over distance and the resulting force is extremely small.

Magnetic levitation with superconductors follows the same principle. The rate of change in the earth's field with altitude and resulting force is extremely tiny.

It's an exciting idea, but unfortunately, it won't work.

I am aware of the inverse square law,but the sun is constantly emitting massive magnetic fields.A CME(Coronal Mass Ejection) would give a spacecraft a big boost,even at great distances.While it may not be possible on Earth,it may be possible in space or orbit to correct decreasing orbits of satellites,for a boost on satellites.Might even be possible to propel a spacecraft in outer space.A small push over a long period can accumulate a lot of speed.

They speak of sails that use solar wind to propel space craft,then why not combine it with magnetic repulsion, and a parabolic shaped dish to gather and focus the magnetic energy.

Magnetic fields of the other planets could also give a boost in speed,similar to the sling-shot method using gravity to gain speed.Perhaps combine the two forces.

Jus' thinkin'

If we were only a few molecules high, you might have something...I don't think you can focus a magnetic field so easily, if at all...To use a magnetic field for sailing you would need a sail that could generate an opposing field...very weak though...the size of the sail would have to be impressively large...

..."The interplanetary magnetic field strength is about 50 microGauss near the Earth (1 AU from the Sun), and near 20 microGauss at a distance of 2 AU from the Sun. The solar wind near 2 AU is about 1 proton / cm³, and flows at ~ 300 km/s (e.g., Baumgärtel et al."...

There is 1 million micro-gauss in a gauss....fyi

https://ned.ipac.caltech.edu/level5/March03/Vallee2/Vallee3_2.html#:~:text=The%20interplanetary%20magnetic%20field%20strength,(e.g.%2C%20Baumg%C3%A4rtel%20et%20al.

So how much force is produced by the solar wind,compared to the theoretical force from a repulsive magnet at the same distance.Solar wind also travels slower than magnetic fields.

The solar-wind sails are enormously large,but size does not really matter in the vacuum of space,and very little friction,except collisions with hydrogen atoms.

If you apply a magnet to an iron bar,the other end of the bar will be magnetized.With the proper shape configuration,magnetic fields can be guided and amplified.

Superconductors repel magnetic fields of either polarity,so they could also be used to steer magnetic fields.

Here is something you might find interesting. Solar wind can be used for propulsion, but you need a very large area sail to get much thrust out of it. The M2P2 project utilizes a magnetic field to trap the solar wind over a large area by generating a magnetosphere similar to that found around planets with magnetic fields.

https://ntrs.nasa.gov/citations/20010071154

https://science.nasa.gov/science-news/science-at-nasa/2000/ast04oct_1/

I was developing a magnetic coupler… I bought some smaller Neodymium Magnets (N52). Quite a learning experience on handling them. First thing is did was pinched my fingers.

Was your second action bending over to pick up the one that shot across the table and over the edge?

No, my second action was trying to take it apart where I pinched myself again, and now I have (3) magnets stuck together because I didn’t have the magnets far enough apart…

Skipping to my 5th action, I broke the magnet trying to get the fourth magnet apart…. .

fortunately, I bought extra magnets…

back to the topic…

Just thinking about this mishap… somewhere turning the magnets on and off, could be a means of propulsions…. If the field is stronger than the magnetic force required to move the mass after the repel/attraction.

Since superconductors repel all polarities of magnetism,and space is cold enough to allow superconductors to function without additional cooling,it would require very little power to repel all magnetic fields. Open space if filled with electromagnetism,small though the may be,but using superconductors to guide and steer the magnetic fields could perhaps generate forward thrust.

I do not know how far the repulsion of the magnetic field extends beyond the superconductor itself,but it could be enough to affect magnetic fields over a large area from a point source;an invisible magnetic sail,in effect.

Imagine a repulsive field extending miles,and yes,I am, aware of the inverse square law,and it would require a lot of energy(perhaps nuclear sourced) input to start the superconductor,but with no resistance to electrical flow,it would stay energized.

I am sure there are external forces that would weaken the field,'cause you can't fool mother nature on energy.Acceleration requires energy,and it must come from somewhere,perhaps requiring more energy input into the superconductor.

Even so,it would not require a large massive fuel supply that diminished over time.

As you may already guess, this is all above my pay grade… I'm just treating this a a brainstorming session…

My initial thought (that turned out to be perpetual motion as I thought about it more), using a form of a pulse, onto (2) objects that’s tethered together.

where bother objects of equal mass are retracted together by a tether…

Then repulsive is pulsed where the two objects are separated.

and then retracted again…

so considering it perpetual motion consider it a passing thought, and treat it as seed for some other idea.

Is there a resistance to bending a magnetic field,as in a rotor of an electric motor?

I think the repelling magnetic field would force the craft out of it's field,l like a linear motor.

If the repelling force is shielded from non-contributing directions,I think you would have propulsion.Maybe not much,but over a long time period it could add up.

The energy would come from the magnetic field itself,not perpetual motion.

The superconductor would weaken,and have to be recharged periodically by an internal energy source.

Does anyone know for certain what happens to a superconductor when it is surrounded by a strong magnetic field?

The concept I imagine would be like a surfer,riding a wave,harnessing the power of the wave,not perpetual motion,per se.

Does anyone know for certain what happens to a superconductor when it is surrounded by a strong magnetic field?

Superconductors can be quenched by too much temperature or too much magnetic field or both. The plots below show the relationship between flux and temperature for type I and type II superconductors.

From http://hyperphysics.phy-astr.gsu.edu/hbase/Solids/scbc.html :

"

Critical Magnetic Field

The superconducting state cannot exist in the presence of a magnetic field greater than a critical value, even at absolute zero. This critical magnetic field is strongly correlated with the critical temperature for the superconductor, which is in turn correlated with the bandgap. Type II superconductors show two critical magnetic field values, one at the onset of a mixed superconducting and normal state and one where superconductivity ceases."

I suspected as much,but could not find a reference.Thanks!

Can a strong alternating magnetic field induce more current to flow in a superconductor,or would the ac magnetic field be repelled by the superconductor,up to the limit of the repelling field of the superconductor?

Neodymium Iron Boron magnets are both very strong and brittle. If they are allowed to snap together, one or both will probably break.

You can't pull those things apart. The only way I know to separate them is by sliding them apart, possibly holding one with a wooden vice.

Yes, you slide them apart,… I broke a couple of them coming up with a way to separate them by sliding them in a table top…. I actually had to make a tool on my 3D printer to separate them…

All because I’d set one down, and it would be too close to another one and plink… when I received it, it came in a stack with insulators between each one that helps separate them…

Simular to a horizontal token/coin chute. A little precarious when I operate it,… because the strongest filament I had was ABS filament. Graphite/ABS filament would work better.

It sounds like the set I bought. Two of them are in use holding an outside temperature sensor that is easy to remove to change the batteries.

HiTek your spirit is in the right place but needs a lot more research which I guess this forum helps with.

These days I happen to work for a factory where we make 3 Tesla electromagnets with superconductors.

It is true that you can charge the magnet and as long as it stays cold it doesn't need any additional power into the coils for years. It does lose power but very slowly.

It all needs to be cold, any minor vibration or added heat (radiation, dust collisions and so on in space) will quickly increase the resistance of a small section which creates heat and a feedback loop so that it will quench the coil very quickly.

The field strength from a 3T magnet is just enough to hold a 5/8" nut on a string horizontal at about 3 feet any more than that and it just drops.

I know you know the math but when you see it in person the field is really impressive and dangerous when you get close but it just drops off so fast with distance as the math shows.

I was really into magnetism when I was younger because its like magic to a kid. I am not saying some sort of magnetic propulsion can't exist but the inverse square law is really a problem here for what you are thinking.

Thanks!Very informative!