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Gear300
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What is magnetism?...preferably no links to other sites...just a conceptual answer...
Sakha said:Why that happens? Someone may say because electron charge and whatsoever, but it is as elemental as we can get. Its like asking what was before the Big-Bang.
Renge Ishyo said:It is part of the electromagnetic force. Strictly speaking, magnetism is the relativistic part of the electric force. This is why you see the velocity in the formula for the magnetic force (and why the force is zero if the particle is at rest with respect to a second magnetic field). The "electric force" and the "magnetic force" are tied together...but you can set up situations where the effect of one or the other seems to predominate. If you want a good mostly non-mathematical explanation of this see R.Feynman's "Lectures on Physics Vol.II - Chapter 1."
jambaugh said:However here's what it is... Magnetism is a component of electromagnetism (which component depending of the observer's inertial frame) which in turn can be described as the force due to a U(1) gauge symmetry of the vacuum. If you add a small circular degree of freedom to any particle in addition to its three spatial translational degrees of freedom and its three rotational degrees of freedom then you must ask how does the particle's orientation in this hidden symmetry change when you move it from point A to point B and or let time pass. The answer is there is some connection between event points which we call the electromagnetic potential. What is this extra degree of freedom? Call it phase, call it another dimension, you can't see it so it's "only a model". It's a darn useful model for describing all the consequences of electromagnetism succinctly but in the end you only can be positive about the observed phenomena.
The other physical forces can similarly be modeled in terms of hidden "gauge" degrees of freedom for particles and these (apart from gravity) together form a model called The Standard Model. Gravity works the same way but the degrees of freedom are not hidden, they are the usual degrees of freedom involved in rotating and translating a particle around.
Could the same be said about the electric force in respect to the magnetic force?
Gear300 said:I lost you there...
jambaugh said:Yes. I beg your pardon. I was being a bit obtuse on purpose. I don't however know where to begin as I don't know where your level of understanding starts.
Renge Ishyo said:If you mean can you set up experiments where each "appears" as a separate force that yes. In fact, this is how you study them in elementary physics so you can look there for the setups. But the electric force and magnetic force are two different aspects of the same thing as the movement of an electric charge generates a magnetic field. If you understand differential equations see Maxwell's equations...it is a set of 4 equations that describe how electricity can cause magnetism and vice versa (and I must say, they are perhaps the most beautiful equations in all of classical physics as they compress all of the knowledge about electricity and magnetism into a few short statements).
Gear300 said:Electricity and Magnetism are 2 aspects of the same phenomenon...so doesn't that imply that we could fuse electricity and magnetism and getting something else...sort of like what was once a more original force that now exists in stability as electromagnetism.
jambaugh said:Not by "fusing electricity and magnetism" per se. They already are "fused" aka unified.
What we mean by "electricity and magnetism being 2 aspects of the same phenomenon" has to do with unifying space and time in special relativity. If you have a bar magnet which is generating a magnetic field then if I'm moving past you I don't see pure magnetism I see a combination of magnetic and electric fields. Similarly if you have a statically charged ball I'll see a moving charge i.e. a current and thus a magnetic field along with the electric.
Now there are attempts to unify electro-magnetism with other forces. Electro-weak unification works quite well although there are some peculiarities begging explanation.
Attempts at unifying these with the strong force usually lead to mechanisms by which protons can decay and several experiments have failed to observe this even at very very low levels of probability. Research has stalled a bit and I suspect a major change of paradigm will be needed to move beyond what we have now which is the Standard Model.
Magnetism is a force that is present in certain materials, such as iron and nickel, that allows them to attract or repel other materials. It is caused by the alignment of the electrons within the material.
Magnetism is caused by the movement of charged particles, specifically electrons, within a material. These electrons align in such a way that creates a magnetic field, which can either attract or repel other materials.
The three main types of magnetism are ferromagnetism, paramagnetism, and diamagnetism. Ferromagnetism is the strongest type and is present in materials such as iron and nickel. Paramagnetism is weaker and is present in materials like aluminum. Diamagnetism is the weakest type and is present in all materials, but is usually masked by the stronger types of magnetism.
Magnetism has many practical uses, including in compasses for navigation, electric motors, and generators. It is also used in magnetic resonance imaging (MRI) machines for medical imaging and in speakers for sound production.
Magnetism can be created by exposing a material to a magnetic field or by inducing a magnetic field through the flow of an electric current. It can also be manipulated by changing the strength or direction of the magnetic field.