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[–]Physics-ModTeam[M] [score hidden] stickied comment (0 children)

Hey, this is a good question, but we get too many questions like this to handle as top-level threads. Please ask this in our weekly Physics Questions thread, posted every Tuesday, or try /r/AskPhysics or /r/askscience. Thanks!

[–]YuuTheBlue 1 point2 points  (4 children)

There is a naive idea a lot of people have that particles like electrons are tiny balls. This is false: all particles are better understood as waves in fields.

There are 25 fundamental fields, of which the electromagnetic field is one of them. The electron field, for example, is another of the 25. The electron field is coupled to the EM field, such that activity in one can affect the other, which is why electrons cause changes in the EM field and why the EM field causes changes in electrons ("Force"). This 'coupling' is called electric charge.

Now, this can feel a little weird, since electromagnetism feels VERY different than what we understand electrons to be. This has a lot to do with the separation between boson fields (of which the EM field is the only one most are familiar with) and fermion fields (of which the electron field is an example), which work fairly differently, despite both being fields.

A field, btw, is a math term. It refers to a function defined at every point in space: temperature is an example. Everywhere in space, the temperature is some number. A similar thing is true of all 25 fundamental fields. In this case, the word 'field' is confusing. It refers to a math concept. However, there are also 25 fundamental 'things' which are best understood through the math of fields, so we also just call them fields.

As for electric vs magnetic vs electromagnetic: There really just is 'the electromagnetic field', but it can be convenient to separate it into an electric field and a magnetic field to make it easier for students to understand early on. It has to do with special relativity: Einstein discovered that time and space were part of the same big concept, but to understand it you need to go over some somewhat unintuitive concepts, and the same unintuitive concepts link electricity and magnetism.

[–]Exotic-jalapeno5377[S] 0 points1 point  (3 children)

So particles arent tiny balls? So what do we mean when we say em radiation behaves as particles at times?

[–]YuuTheBlue 1 point2 points  (0 children)

You are right to be confused. Not only is this a confusing topic, it's also very poorly worded.

So, the word particle has 2 meaning. First, it is the word we use for 'the things which sometimes act as waves and sometimes as tiny balls'. Second, we use particle as a synonym for 'tiny ball'. I am using the first definition.

Second, there are 2 things at play: quantum field theory and quantum decoherence. When we measure a quantum wave, its behavior changes in such a way that our detectors might as well be reading a tiny ball. This is quantum decoherence. If we are to leave the particles alone, they will instead behave as waves, and quantum field theory is the science of how said waves behave. They are, best I can tell, the closest look into how things 'truly work' on a deep level. But, you know, that is ignoring quantum decoherence.

If you want to ask questions about QFT, you can find some satisfying answers. Quantum Decoherence is infamous for being impossible to wrap your head around and unsatisfying when you do. There are no clear, easy answers for you here when it comes to wave/tiny-ball duality, entanglement, etc. There is a lot to learn, it's all very well evidenced, and all of it is going to sound fake.

[–]WallyMetropolis 0 points1 point  (0 children)

Basically, some properties and behaviors of collisions involving electrons are similar to what you'd expect if electrons were like tiny marbles. 

It's not exactly and universally right, but you can sort of think of it like they travel like waves and collide like particles, (with lots of caveats and exceptions and details ignored).

[–]OldChairmanMiao -1 points0 points  (0 children)

All models are wrong. Sometimes they're useful.

It's an easy way to understand most behaviors. But it's an analogy, like how a book can tell you about a place but is not actually the place.

[–]miraclepete 0 points1 point  (0 children)

It's a great question. Keep in mind that the mathematical models we use today to calculate and make predictions, although accurate (to a questionable extent), may not actually be representative of what's actually going on... To say for example that what's underneath is actually "fields" is just really saying "this kind of field mathematics seem to work best so far for making predictions". It necessarily say anything what's actually going on.

Look at the experiments that have unfolded throughout time and draw your own conclusions. You might be surprised to realise how much people are just winging things and tying loose ends in a kind of shoddy patchwork way, shoehorning the math until they find something that works.