posted on Mar, 14 2013 @ 03:52 PM
Originally posted by mbkennel
Yes, this is known as a "classical field theory". Gravity and magnetism are the principal examples. (Not only that, the 2nd volume of Landau & Lif#z
textbook is called "The Classical Theory of Fields" and contains both electromagnetism & gravity).
Here's what's going on with magnetism. In a permanent magnet (ferromagnet, for example which is what most people associated with "a magnet") some
special quantum mechanics makes it such that there are a large number of electrons with their spin pointing in the same direction.
It is an intrinsic property of nature that electrons create a magnetic field, just by their existence sitting there without moving. There is no
deeper explanation, as far as we know, it is a fundamental property of elementary particle physics, called the magnetic moment and it points in the
same direction as its intrinsic angular momentum, called spin.
Even though the electron is considered a point, the magnetic field generated by its spin extends over space.
Classically, there is only one value of the magnetic field at all points in space and time. When you have a large number of electrons with spin in the
same direction, the magnetic fields they create add up to make a macroscopically observable magnetic field.
Now, the spins/magnetic moments which are part of the other material have an interaction with the external magnetic field. The potential energy of
this interaction depends on the field strength, the field orientation and the orientation of the dipole. If this energy has a non-zero gradient with
distance (as it usually is) then there will be a net force either attracting or repelling the magnets.
Calculating this type of thing is a classic problem in undergraduate electromagnetism classes.
Yes thank you for that response. So with field theory, it is known that it is energy/matter's interaction with space which causes the field or no?
like a planet creates a field, which is a distortion in space which causes gravity. And magnetism, electrons create a field, which is a distortion in
space which causes magnetism? And, maybe even light can said to be a distortion of space caused by an accelerated charge. Is a magnetic field made of
em radiation? or is that a silly thing to ask because em radiation is made of a magnetic field...
I just want to know the truth, and I dont want to read a whole text book right now to do it, it should be able to be stated simply. Either magnetism
works by electrons causing activity of space which allows magnetic properties to exist. Or magnetism works by the electrons physically touching the
electrons of another material them selves and either pushing them away or pulling them toward. Which one do you think it is?
If electrons interact with local space and that is how magnetism works, this is perhaps an analogy that can explain it...maybe...
2 rectangular wooden blocks of equal size, with 100 mini water wheels on each block, which all have motors which cause them to constantly spin, they
are all facing the same direction/spinning same direction on each block. if you held one in your hand from the top and placed it in water you would
get two different style wakes from the front in back. If you placed the equal other block with both back ends facing the created wakes or distortions
would push away from one another; if you put the fronts together i think they might repel as well, because both items would have an inward pull of
space so when placed together neither would want to completely go towards the other. If you placed opposite ends, it would be an outward wave, plus
an inward wave and perhaps the inward wave would climb the outward wave like a ladder, or get attracted like a rip tide, or like how if you are
standing in a pool you can get an object out of reach, in reach, by making motions in your local water space. If the electron spins in magnets arent
aligned vertical spins like that in the total magnetic domain and they are spinning perpendicular to the long ways of the rectangular direction, then
this analogy may also be relevant to understand the repulsive and attractive forces of 2 bar magnets. And I think this would have to do with half way
point of an object like a rectangle or sphere, cuts the object into 2 perspectives in a way. If you look down on a sphere spinning clockwise, and
then keep the sphere spinning the same, but look up at it, its spinning counter clockwise. This would cause waves (if any) to spin outward and
downward with different directions of angular momentum. So if electrons spin perpendicular to the long ways of a rectangular bar magnet, then looking
down at the magnet, the electrons spin would be in one direction, and looking up at it would be spinning the opposite direction.
14-3-2013 by ImaFungi because: (no reason given)