As my knowledge of physics increases I begin to come up with ever complicated questions… things my physics teacher usually can’t answer. So, the other day we were studying magnetism and it was bother me that the electronic force and its force particle cause two semi-distinct types of forces: magnetic and electrical. So, why doesn’t the strong nuclear force have two manifestations? Or does it? What about gravity? Is it feasibly possible under todays understanding of physics that gravity has a magnetic like counterpart? (possibly the cause behind the apparent antigravitational expansion of the universe?)
My physics teacher said he read an article that stated the data is indicating that, not only is the universe expanding, but it’s accelerating outward. Maybe the ‘force’ behind this is another property of gravitrons. I was also thinking that there might be a 5th force that acts on a larger scale than gravity, but that would be kinda off the wall. So does anyone know the current explanation for the expansion? Why is gravity so weird?
Oh, on another note: I read in popular science that they are looking the “God Particle”, which would be the cause of mass, so to speak. To anyone familiar with string theory, do you think this would void the whole theory? After all, according to Bryan Greene mass is caused by oscillations in the strings.
Sorry if this seems to much like ranting, but I’m just trying to get feedback on some ideas.
It is interesting that you labeled this thread “…and the 4 Forces,” since one of those four forces is the electromagnetic force. It just depends upon how you look at it.
Yes, the strong and weak forces have magnetic counterparts. Briefly, moving particles create different fields than stationary particles. Same for gravity.
These are usually not discussed because
They are considered part of the force itself, just like electric and magnetic forces are considered part of electromagnetism,
Strong and weak forces act at the quantum level, so classical “field” descriptions are usually not very useful. Forces are caused by exchange of particles (field quanta).
In the case of gravity, the magnetic component is extremely weak and hasn’t yet been measured AFAIK.
To amplify on FriendRob’s reply, in special relativity (SR) the distinction between electric and magnetic fields becomes somewhat fluid. Which you think is which depends on how you’re moving. The more natural quantity to consider in SR is a combination of these fields, usually refered to as the “4-vector potential” or similar. This is because there’s a sense in which this doesn’t depend on how you’re moving. When one comes to worry about quantum field theory, then this 4-vector becomes the basic way of thinking about electromagnetism, so quantum field theorists really don’t habitually think about separate electric and magnetic fields. Everything’s much simpler in terms of the 4-potential, so that’s how they conceptualise things.
As you may know, the strong nuclear force is actually a consequence of the force between the quarks making up nuclear particles like protons and neutrons. This force between quarks is described by a quantity analogous to (but more complicated than) the electromagnetic 4-potential. It’s not “natural” to a quantum field theorist to split this into “electric” and “magnetic” parts (after all, the whole historic thrust was to get away from this split), but it can be done. As far as I can tell, that splitting was sort of popular back in the 70s when this theory (QCD) had just been introduced and people wanted an “intuitive” analogue. You occasionally get it still, but that’s rare.
Well, gravity’s weird for all sorts of reasons. On the particular question, standard gravitons lead to general relativity, so can’t be an explanation of any accelerating expansion. People play around with alternatives, but there doesn’t appear concensus just yet.
It’s a while since I looked at any string theory, but from memory different oscillations produce different types of massless particles. One of these will be a Higgs-like particle (the “God particle” as no physicist refers to it) or particles. By interacting with the other particles, this appears to give them mass. There’s thus no contradiction between the two ideas - and indeed string theory has been heavily influenced by the Higgs idea.
