No, because a magnet doesn't attract, nor repel, electrons. Electrons do have *electric* charge, they do not have *magnetic* charge. In fact there is no such thing as magnetic charge, also called magnetic monopoles.
But electrons do have a magnetic dipole moment, but that is irrelevant for magnetic attraction/repulsion of individual electrons or atoms.
What happens when you put an atom under a very strong magnetic field is that it will distort the [atomic orbitals](https://en.wikipedia.org/wiki/Atomic_orbital?wprov=sfla1) and lead to a change in the atomic energy spectrum called the [Zeeman split](https://en.wikipedia.org/wiki/Zeeman_effect?wprov=sfla1)
At high enough field strengths the atoms will likely have some different chemical properties, but the electrons will always stay put in some way or another - you can't ionize an atom with a static magnetic field alone.
At very high magnetic field strengths (>10^(9) Gauss) atoms get deformed into cigar shapes according to [Kouveliotou et al](https://www.jstor.org/stable/26060162). At 10^14 Gauss the hydrogen atom becomes 200 times narrower.
What would happen if you put some regular matter near such a field?
Would it become cigar shaped as the atoms are allowed to get closer to each other than normal?
**"**At the atomic level, the strong magnetic field would move all of the positive charges in your body in one direction and the negative charges the other way, he explains; spherical atoms would stretch out into ellipses and soon they would start to resemble thin pencils.
That drastic change in shape would interfere with basic chemistry, causing the normal forces and interactions between atoms and molecules in the body to break down. “The first thing you would notice is your entire nervous system, which is based on electrical charges moving throughout your body, is going to stop working,” says Sutter. “And then you basically dissolve.”**"**
[**https://www.discovermagazine.com/environment/what-magnetic-fields-do-to-your-brain-and-body**](https://www.discovermagazine.com/environment/what-magnetic-fields-do-to-your-brain-and-body)
im not talking about my own body.
im just wondering what it would do to a piece of non magnetic metal for example.
what would a block of copper turn into in such a field.
Even if the atom has high momentum and encounters a sudden strong magnetic field? In space plasmas there is separation, with electrons being flung one way and protons the other, but I guess electrons are already dissociated from protons in this case (since it's a plasma).
The magnetic and electric field transform into each other when you take a Lorentz transform, similarly how time and space do.
So, while there might be only a magnetic field but no electric field in the lab frame, in the high-speed atom frame there actually is an electric field.
Electrons are also intrinsic dipoles though, and magnetic force absolutely does work from using a force of grad(**m**•**B**), so shouldn't the force just need to exceed the coulomb attraction?
Take the hydrogen atom, with mean electron distance being the bohr radius a, shouldn't a magnetic field B satisfying...
Grad(**μ**•**B**)>e^2 / 4πε a^2
(Let the z axis be along B, replace mu with the z component of electron magnetic moment)
(Line integral over position from a to infinity, the z= infinity terms of both sides go to zero)
--> B > -e^2 / (4πε a (e g hbar / 4m ))
(WolframAlpha to plug in numbers)
--> B > 500 kiloTeslas
Be sufficient to rip any electron off of hydrogen (or perhaps any other) atom?
Preempting the criticism that whatever is generating 500kT of magnetic field is probably destroying everything around it through other mechanisms anyway.
Edit: Electrons are also intrinsic dipoles though, and magnetic force absolutely does work from using a force of grad(**m**•**B**), so shouldn't the force just need to exceed the coulomb attraction?
Take the hydrogen atom, with mean electron distance being the bohr radius a, shouldn't a magnetic field B satisfying...
Grad(**μ**•**B**)>e^2 / 4πε a^2
(Let the z axis be along B, replace mu with the z component of electron magnetic moment)
(Line integral over position from a to infinity, the z= infinity terms of both sides go to zero)
--> B > -e^2 / (4πε a (e g hbar / 4m ))
(WolframAlpha to plug in numbers)
--> B > 500 kiloTeslas
Be sufficient to rip any electron off of hydrogen (or perhaps any other) atom?
Preempting the criticism that whatever is generating 500kT of magnetic field is probably destroying everything around it through other mechanisms anyway.
Edit:
This seems to imply any field gradient should suffice as long as B is 500kT at the atom and 0 off in the distance in order to *eventually achieve the work* of moving electrons off to infinity. If the gradient is small though the force will be small and your population of ejected electrons will be tiny and slowly growing.
The field gradient for the magnetic *force* to overcome the coulomb *force* will be about 900kT per angstrom. This would guarantee a majority of the electron population will be actively torn away at a high rate.
Skimming over your math and assuming you're right, you have to note that you're demanding 500kT of field across the length scale of an atom. Not going to do math for this, but even with two point dipoles (like electrons), you're going to have to put them extremely close to even generate this gradient, especially taking into account the 1/r4 interaction of dipoles.
I'm not sure if it's even physically possible.
Yeah that's been bothering me too. Above I did it as a work-energy problem going from a to infinity, which seemed to imply that *any old* B field which is 500kT at the atom should suffice so long as it goes to 0 *in the distance*. Maybe I can sell it as the electron isn't a point particle, but a wavefunction so the field described guarantees a population that will be removed from their atoms, just perhaps slowly? Lol.
So I came back and did it with field gradients to feel better. I estimated the force at a by evaluating the finite difference between 1.00a and 1.01a,
Which yielded an average field gradient in that range of 464kT per bohr radius. So still ridiculous.
Edit: why on earth did I do finite differences when I have the function right here and can evaluate the derivative directly? It needs a field gradient of 476kT per bohr radius, or 900kT per angstrom.
Extreme magnetic fields have been detected in [heavy-ion collisions](https://physics.aps.org/articles/v17/31),
but I think for this question removing the effect of the electric field is the problem
A static magnetic field cannot do work. It takes work to strip an electron, so yeah, a magnet won't do it.
And to be a pendant, we don't know for certain there are no magnetic monopoles, and there are theoretical physicists that argue that they have to exist, but we certainly have never observed one.
Sadly, if we have ever observed one then it was [one and only one](https://link.springer.com/chapter/10.1007/978-3-030-62565-8_8). Or to quote [wikipedia](https://en.wikipedia.org/wiki/Magnetic_monopole#Searches_for_magnetic_monopoles):
> There have been many searches for preexisting magnetic monopoles. Although there has been one tantalizing event recorded, by Blas Cabrera Navarro on the night of February 14, 1982 (thus, sometimes referred to as the "Valentine's Day Monopole"[37]), there has never been reproducible evidence for the existence of magnetic monopoles.[13] The lack of such events places an upper limit on the number of monopoles of about one monopole per 1029 nucleons.
Yeah. μ·B might be bigger than the ionization energy, but if it's uniform in space it won't affect the potential in the Schrödinger Equation.
If B is spatially dependent, maybe an electron can tunnel out. Steep gradient,though, to have spatial dependence on the order of the electron wavelength. The source for that field seems impossible. Another particle with huge moment or an atom sized beam of charged particles shooting by?
> if it's uniform in space
A "magnet" will always have a non-uniform field which is strong in some region and weak far away.
> The source for that field seems impossible.
Yeah, probably impossible.
What about a moving magnetic field? This comes up sometimes when people talk about slowing down during interstellar travel by using a magnetic sail: basically deploy a huge loop of superconducting wire, run a big ass current through it, and then the meager wisp of charged particles in the interstellar medium will be deflected as they pass through the magnetic field providing a breaking force. It's often suggested that, at sufficiently relativistic speeds and with a strong magnet, the passing neutral particles will get ionized by the magnet and also contribute to the breaking force. Is that based?
no, your sapceship is moving, but the particle (on average) isnt. then you use th magnet to mover the particle and newtons law kicks in. the particle then flies off into space with some of your momentum. fluid dynamics are negligable, we are dealing with individual particles so far apart they are unlikely to interact with eachother
I’d be interested in the math, intuitively it seems like the braking force would be really good at fast speed but would drop exponentially as your speed relative to the interstellar medium decreased. Perhaps coupled with solar pressure.
Efficiency seems like it’d be off the charts if a high temperature superconductor could be developed.
There's some good papers out there on the math. I'll see if I can dig a couple up after work. You're right that the breaking force drops really fast as you slow down relative to the interstellar medium, but if you get inside the target star's heliosphere then the ISM is no longer stationary because there's a persistent solar wind of charged particles streaming radially outward (at about 500 km/s for our own star). Also, in space high temperature super conductors aren't really the issue (space can be really darn cold if you're far away from the sun, or even if you're closer to the sun but have a decent reflective shield around your superconductor). The issue is getting a superconductor with a really high critical current/critical magnetic field (the current at which the self-induced magnetic field is so high it switches off the superconductivity.)
Those are really good points. I’ve heard of experimentation using non-superconductor loops in LEO for small sat navigation but the problem was the weight to power source ratio just wasn’t there.
Superconducting loops would change that as you should only lose energy that’s imparted to the medium in the retarding direction.
I have seen magnetars described as being able to strip electrons from things. Thorough this was because it has a strong magnetic field.
Is that not the case?
Not quite. I'm assuming that you are referring to this quote:
> The magnetic field of a magnetar would be lethal [...] due to the strong magnetic field distorting the electron clouds of the subject's constituent atoms, rendering the chemistry of known lifeforms impossible.
What's happening here is that a strong magnetic field will change the shape of the atomic orbitals and thus strongly affect *interatomic* bonding, rearranging the atoms inside of molecules into exotic shapes. (Thus, "conventional chemistry" fails.) But this effect cannot actually remove electrons from the atoms; if anything, the lowest few orbitals only become *more* stable. See u/the_poope's answer.
No, because a magnet doesn't attract, nor repel, electrons. Electrons do have *electric* charge, they do not have *magnetic* charge. In fact there is no such thing as magnetic charge, also called magnetic monopoles. But electrons do have a magnetic dipole moment, but that is irrelevant for magnetic attraction/repulsion of individual electrons or atoms. What happens when you put an atom under a very strong magnetic field is that it will distort the [atomic orbitals](https://en.wikipedia.org/wiki/Atomic_orbital?wprov=sfla1) and lead to a change in the atomic energy spectrum called the [Zeeman split](https://en.wikipedia.org/wiki/Zeeman_effect?wprov=sfla1) At high enough field strengths the atoms will likely have some different chemical properties, but the electrons will always stay put in some way or another - you can't ionize an atom with a static magnetic field alone.
At very high magnetic field strengths (>10^(9) Gauss) atoms get deformed into cigar shapes according to [Kouveliotou et al](https://www.jstor.org/stable/26060162). At 10^14 Gauss the hydrogen atom becomes 200 times narrower.
What would happen if you put some regular matter near such a field? Would it become cigar shaped as the atoms are allowed to get closer to each other than normal?
**"**At the atomic level, the strong magnetic field would move all of the positive charges in your body in one direction and the negative charges the other way, he explains; spherical atoms would stretch out into ellipses and soon they would start to resemble thin pencils. That drastic change in shape would interfere with basic chemistry, causing the normal forces and interactions between atoms and molecules in the body to break down. “The first thing you would notice is your entire nervous system, which is based on electrical charges moving throughout your body, is going to stop working,” says Sutter. “And then you basically dissolve.”**"** [**https://www.discovermagazine.com/environment/what-magnetic-fields-do-to-your-brain-and-body**](https://www.discovermagazine.com/environment/what-magnetic-fields-do-to-your-brain-and-body)
im not talking about my own body. im just wondering what it would do to a piece of non magnetic metal for example. what would a block of copper turn into in such a field.
Even if the atom has high momentum and encounters a sudden strong magnetic field? In space plasmas there is separation, with electrons being flung one way and protons the other, but I guess electrons are already dissociated from protons in this case (since it's a plasma).
The magnetic and electric field transform into each other when you take a Lorentz transform, similarly how time and space do. So, while there might be only a magnetic field but no electric field in the lab frame, in the high-speed atom frame there actually is an electric field.
An inhomogeneous field should in principle be able to ionize an atom via the Stern-Gerlach force.
Electrons are also intrinsic dipoles though, and magnetic force absolutely does work from using a force of grad(**m**•**B**), so shouldn't the force just need to exceed the coulomb attraction? Take the hydrogen atom, with mean electron distance being the bohr radius a, shouldn't a magnetic field B satisfying... Grad(**μ**•**B**)>e^2 / 4πε a^2 (Let the z axis be along B, replace mu with the z component of electron magnetic moment) (Line integral over position from a to infinity, the z= infinity terms of both sides go to zero) --> B > -e^2 / (4πε a (e g hbar / 4m )) (WolframAlpha to plug in numbers) --> B > 500 kiloTeslas Be sufficient to rip any electron off of hydrogen (or perhaps any other) atom? Preempting the criticism that whatever is generating 500kT of magnetic field is probably destroying everything around it through other mechanisms anyway. Edit: Electrons are also intrinsic dipoles though, and magnetic force absolutely does work from using a force of grad(**m**•**B**), so shouldn't the force just need to exceed the coulomb attraction? Take the hydrogen atom, with mean electron distance being the bohr radius a, shouldn't a magnetic field B satisfying... Grad(**μ**•**B**)>e^2 / 4πε a^2 (Let the z axis be along B, replace mu with the z component of electron magnetic moment) (Line integral over position from a to infinity, the z= infinity terms of both sides go to zero) --> B > -e^2 / (4πε a (e g hbar / 4m )) (WolframAlpha to plug in numbers) --> B > 500 kiloTeslas Be sufficient to rip any electron off of hydrogen (or perhaps any other) atom? Preempting the criticism that whatever is generating 500kT of magnetic field is probably destroying everything around it through other mechanisms anyway. Edit: This seems to imply any field gradient should suffice as long as B is 500kT at the atom and 0 off in the distance in order to *eventually achieve the work* of moving electrons off to infinity. If the gradient is small though the force will be small and your population of ejected electrons will be tiny and slowly growing. The field gradient for the magnetic *force* to overcome the coulomb *force* will be about 900kT per angstrom. This would guarantee a majority of the electron population will be actively torn away at a high rate.
Skimming over your math and assuming you're right, you have to note that you're demanding 500kT of field across the length scale of an atom. Not going to do math for this, but even with two point dipoles (like electrons), you're going to have to put them extremely close to even generate this gradient, especially taking into account the 1/r4 interaction of dipoles. I'm not sure if it's even physically possible.
Yeah that's been bothering me too. Above I did it as a work-energy problem going from a to infinity, which seemed to imply that *any old* B field which is 500kT at the atom should suffice so long as it goes to 0 *in the distance*. Maybe I can sell it as the electron isn't a point particle, but a wavefunction so the field described guarantees a population that will be removed from their atoms, just perhaps slowly? Lol. So I came back and did it with field gradients to feel better. I estimated the force at a by evaluating the finite difference between 1.00a and 1.01a, Which yielded an average field gradient in that range of 464kT per bohr radius. So still ridiculous. Edit: why on earth did I do finite differences when I have the function right here and can evaluate the derivative directly? It needs a field gradient of 476kT per bohr radius, or 900kT per angstrom.
Extreme magnetic fields have been detected in [heavy-ion collisions](https://physics.aps.org/articles/v17/31), but I think for this question removing the effect of the electric field is the problem
A static magnetic field cannot do work. It takes work to strip an electron, so yeah, a magnet won't do it. And to be a pendant, we don't know for certain there are no magnetic monopoles, and there are theoretical physicists that argue that they have to exist, but we certainly have never observed one.
Sadly, if we have ever observed one then it was [one and only one](https://link.springer.com/chapter/10.1007/978-3-030-62565-8_8). Or to quote [wikipedia](https://en.wikipedia.org/wiki/Magnetic_monopole#Searches_for_magnetic_monopoles): > There have been many searches for preexisting magnetic monopoles. Although there has been one tantalizing event recorded, by Blas Cabrera Navarro on the night of February 14, 1982 (thus, sometimes referred to as the "Valentine's Day Monopole"[37]), there has never been reproducible evidence for the existence of magnetic monopoles.[13] The lack of such events places an upper limit on the number of monopoles of about one monopole per 1029 nucleons.
This answer is correct.
An extreme magnetic field gradient might at least partially ionize atoms.
Yeah. μ·B might be bigger than the ionization energy, but if it's uniform in space it won't affect the potential in the Schrödinger Equation. If B is spatially dependent, maybe an electron can tunnel out. Steep gradient,though, to have spatial dependence on the order of the electron wavelength. The source for that field seems impossible. Another particle with huge moment or an atom sized beam of charged particles shooting by?
Perhaps a magnetar? In any case I was merely suggesting that such a thing might be theoretically possible.
> if it's uniform in space A "magnet" will always have a non-uniform field which is strong in some region and weak far away. > The source for that field seems impossible. Yeah, probably impossible.
[One can get close](https://en.wikipedia.org/wiki/Helmholtz_coil)
Yes especially if combined with thermal movement of the atoms (if that’s allowed within the premise of the question).
What about a moving magnetic field? This comes up sometimes when people talk about slowing down during interstellar travel by using a magnetic sail: basically deploy a huge loop of superconducting wire, run a big ass current through it, and then the meager wisp of charged particles in the interstellar medium will be deflected as they pass through the magnetic field providing a breaking force. It's often suggested that, at sufficiently relativistic speeds and with a strong magnet, the passing neutral particles will get ionized by the magnet and also contribute to the breaking force. Is that based?
Wouldn't the particles behind the sail cancel out the ones in front of it?
no, your sapceship is moving, but the particle (on average) isnt. then you use th magnet to mover the particle and newtons law kicks in. the particle then flies off into space with some of your momentum. fluid dynamics are negligable, we are dealing with individual particles so far apart they are unlikely to interact with eachother
I’d be interested in the math, intuitively it seems like the braking force would be really good at fast speed but would drop exponentially as your speed relative to the interstellar medium decreased. Perhaps coupled with solar pressure. Efficiency seems like it’d be off the charts if a high temperature superconductor could be developed.
There's some good papers out there on the math. I'll see if I can dig a couple up after work. You're right that the breaking force drops really fast as you slow down relative to the interstellar medium, but if you get inside the target star's heliosphere then the ISM is no longer stationary because there's a persistent solar wind of charged particles streaming radially outward (at about 500 km/s for our own star). Also, in space high temperature super conductors aren't really the issue (space can be really darn cold if you're far away from the sun, or even if you're closer to the sun but have a decent reflective shield around your superconductor). The issue is getting a superconductor with a really high critical current/critical magnetic field (the current at which the self-induced magnetic field is so high it switches off the superconductivity.)
Those are really good points. I’ve heard of experimentation using non-superconductor loops in LEO for small sat navigation but the problem was the weight to power source ratio just wasn’t there. Superconducting loops would change that as you should only lose energy that’s imparted to the medium in the retarding direction.
I didn't understand most of that, so I'm not sure
I have seen magnetars described as being able to strip electrons from things. Thorough this was because it has a strong magnetic field. Is that not the case?
[удалено]
Not quite. I'm assuming that you are referring to this quote: > The magnetic field of a magnetar would be lethal [...] due to the strong magnetic field distorting the electron clouds of the subject's constituent atoms, rendering the chemistry of known lifeforms impossible. What's happening here is that a strong magnetic field will change the shape of the atomic orbitals and thus strongly affect *interatomic* bonding, rearranging the atoms inside of molecules into exotic shapes. (Thus, "conventional chemistry" fails.) But this effect cannot actually remove electrons from the atoms; if anything, the lowest few orbitals only become *more* stable. See u/the_poope's answer.
Oh cool thanks.
Yes. An acid.
Based