I will try my best to explain this question because I’ve googled multiple times over a decade and have asked a physics PhD and neither could understand what I meant, nor answered the question.
I understand that Photons are wave-particles. The smaller the wavelength, the more frequency. I also know that electromagnetism are 2 of the “same thing”, using the same force particle, a photon.
So what frequency do photons that are a acting as strictly magnetic? Magnetism seems to penetrate a heck of a lot more things than even gamma rays (excluding some metals), so why’s that? What makes them different, if they’re the same particle? Are magnetism photons “straight” or act more as a particle than a wave? Do magnetic photons experience the Doppler Effect? If we can count light photons with special instruments, can we do the same with magnet photons? What causes magnetic photons to “bend” around a magnetic object? Like if there was an MRI machine, does that mean there are just a LOT more magnetic photons or is the amplitude of them greater? Can magnetic photons turn into light photons directly?
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Photons are photons.
The only reason an electric field and a magnetic field are different is:
An electric field is created by charged particles that are *stationary*.
A magnetic field is created by charged particles that are *moving*.
That’s it, they are still created by and made of the same thing they just have different properties.
Just like how a car that isn’t moving is basically just a place to store stuff and a car that’s moving is a means of transportation. But they are both still *cars.*
Magnetic *fields* are not photons. Photons are oscillating and moving electromagnetic fields. There is no such thing as a “magnetic photon”.
Changes in a magnetic field can *emit* photons, but the field itself is not photons.
Photons are “wave-particles”, but so is everything else (at least, all fundamental particles).
All particles also sometimes have wave-like properties. The bigger the wavelength (smaller the frequency) something has the more wave-like it is, and the smaller the wavelength the more particle-like it is. This is why high-frequency/low-wavelength photons (gamma particles) act notably particle-like, while low-frequency/high-wavelength photons (radio waves) act very wave-like.
There is a thing called a de Broglie wavelength (named after Louis de Broglie, pronounced more like “broy”, boy with an r), which is inversely proportional to something’s momentum. The more momentum it has the smaller a wavelength, the more particle-like. You, a person, with an awful lot of mass (compared with an electron, say), have a really small wavelength, so act very much like a particle. Photons, electrons, neutrons, atoms, even decently-sized molecules have all been observed to have wave-like behaviour in the right circumstances.
None of which really matters here, but anyway…
Magnetism is complicated. One way of thinking about it is as the correction we have to make to electric forces to account for things moving. We get magnetic fields when we have accelerating charges, or changing electric fields. But by shifting perspective an effect due to an electric field can become an effect due to a magnetic field; they are different ways of looking at the same thing. Which means your question:
> So what frequency do photons that are a acting as strictly magnetic?
isn’t quite right. We cannot get a photon that is strictly dealing with magnetism, because if *we* shift perspective (where the photon will look exactly the same) it might become an electric photon. They are the same thing. The answer to what frequency it has is that it depends on the energy being transferred. The frequency of a photon is directly proportional to its energy; more energy, higher frequency (more particle-like). Low-energy photons carrying a(n electro-)magnetic interaction will be very wave-like. Magnets tend not to transfer that much energy, so they tend to be fairly wave-like.
> What causes magnetic photons to “bend” around a magnetic object?
They don’t. Magnetic *fields* bend around magnetic objects, but fields are mathematical tools physicists use to help model and understand phenomena. I would say that the fields themselves aren’t real, except when we get into quantum mechanics the line between “just a mathematical tool” and “physical reality” become a bit more blurry that we might like.
The other thing we need to talk about is **virtual particles**. When we think of magnets interacting via photons, we’re usually talking about virtual photons rather than “real” photons.
Virtual particles are like real particles, but they are only temporary, cannot exist on their own, and only exist in an awkward quantum-mechanically-uncertain way. They are used to make the maths of quantum field theory work, but cannot be observed or detected on their own. So… aren’t really real, just being mathematical tools. Except, again, that disclaimer about “just a mathematical tool” when it comes to quantum mechanics.
So those “magnetic photons” are photons, but probably also virtual photons. Which are complicated. But the maths works… honest!
You are talking about the distinction between photons that make up visible light, vs. photons as force carrier particles of the electromagnetic force?
The photons that transmit electric forces between charged particles are virtual photons. More information here if you’re curious: [https://en.wikipedia.org/wiki/Virtual_photon#:~:text=Virtual%20photons%20are%20thought%20of,other%20by%20exchanging%20virtual%20photons](https://en.wikipedia.org/wiki/Virtual_photon#:~:text=Virtual%20photons%20are%20thought%20of,other%20by%20exchanging%20virtual%20photons).
I think part of your misunderstanding has to do with a layfolk misconception of wave-particle duality. A lot of people take it to mean you can choose whichever you want, and then they naturally choose to think of light as made up of tiny balls of light called photons because that jives with hunter gatherer on the plains of Africa scale things. These photons being in multiple places at once to interact with themselves and other weird shit is then just tossed into the weird QM realm.
The actual case is the opposite. Light is absolutely not particles travelling through space and absolutely is waves propagating through the EM field. It’s only when these waves interact with stuff that we are forced to consider photons to fit EMR with our particle models.
Now we’re often mostly interested in interactions so you definitely do see photons used a lot in the standard model or whatever. In a sense though it doesn’t really make sense to even consider photons as a thing outside of the moment of interaction. “This interaction emits a photon which we immediately start considering as a wave in the EM field.”
If you can wrap your head around that then I think it becomes pretty obvious that a magnetic photon is also not a thing.
* So what frequency do photons that are a acting as strictly magnetic?
If you are holding a normal bar magnet, and waving it around, the frequency will; be extremely low. And it won’t be pure magnetism: the movement will generate an electric field, which (because it’s also moving) generates a magnetic field and so on. But the frequency will be ridiculously low.
If you aren’t moving it *at all*, it’s not an electromagnetic wave, it’s just an electromagnetic field with no electrical component.
* Magnetism seems to penetrate a heck of a lot more things than even gamma rays (excluding some metals), so why’s that?
Different frequencies of electromagnetic radiaton penetrate different amounts into different materials. The details depend a lot on the exact type of material. Visible light, for example, can interact with a molecule’s electron cloud, and get scattered. A static magnetic field doesn’t interact very much with anything except (say) ferromagnetic materials such as iron, or with electric currents (eg, in an electromagnet)
* What makes them different, if they’re the same particle?
To interact with matter, a photon often has to have just the right amount of energy for the matter to absorb. Some matter can absorb pretty much any frequency, which is why a metal box will shield radio waves etc, and metal makes a serviceable mirror when polished. Others materials are more “choosy”, eg glass (and carbon dioxide) absorb heat radiation much more readily than they absorb visible light.
The energy of a photon depends on its frequency. So different frequencies of light are absorbed differently by different materials. Our whole sense of colour vision depends on this fact.
* Are magnetism photons “straight” or act more as a particle than a wave?
A static magnetic field acts more like a static field than a photon. You’ll only get photons when you start waving the magnet around. And then, since the frequency of each is so low, each one has such low energy that you get zillions and zillions of them to carry away the tiny amount of electromagnetic energy your waving magnet emits. Sicne there are so many, collectively they act just like a wave.
* Do magnetic photons experience the Doppler Effect?
Yes. If you swing the magnet 1 time per second, someone approaching at a high speed might see an electromagnetic wave with a higher frequency. If they’re approaching fast enough, it might even appear as visible light.
If you have a static magnetic field, someone moving across it at high speed will experience it as a static part magnetic, part electric field. That’s one way to understand why a wire with a current gets affected by a magnetic field – the electrons are moving, so they don’t just see a magnetic field: part of it looks to them like an electric field.
* If we can count light photons with special instruments, can we do the same with magnet photons?
A static magnetic field is better thought of as a field. A photon is what you get when the fields are changing in a way that they keep generating changing fields of the other type. Or, using more technical terms, a photon is an “excitation” of the field.
* What causes magnetic photons to “bend” around a magnetic object?
The field exists in all places (even if it’s zero in some places), so it doesn’t “bend” exactly. However, the *direction it points* might be different at different places, so if we trace “field lines” by tracing the direction the field points, those field lines can bend.
* Like if there was an MRI machine, does that mean there are just a LOT more magnetic photons or is the amplitude of them greater?
A photon doesn’t have an amplitude. To have more electromagnetic energy, you either need (a) higher frequency photons, or (b) more photons.
* Can magnetic photons turn into light photons directly?
I’m getting the impression that what you think of as a “magnetic photon” is actually just the “magnetic field”.
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