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What experiment shows that to be the case? What experiment shows that electromagnetism isnt a consequence of a smooth electric field that acts over a distance, but that it is "grainy" in nature? I know photons carry quantized amounts of energy, but what experiment connects them to electromagnetism?
The classic experiments that caused Albert Einstein to realise that electromagnetism must be quantised into photons was the photoelectric effect. He won the Nobel prize for this work and not the theory of relativity. When you shine a light at the surface of some materials it is possible to expel electrons from the surface of the material. This photoelectric effect was used for light sensors before the current solid state devices were developed. The amount of electrons expelled depends on both the intensity and the frequency of the light but there is a threshold frequency below which no electons will be emitted however intense the light radiation is and if the radiation has a high enough frequency or short enough wavelength some electrons will be expelled however weak the radiation is. Different materials have different threshold frequencies. This result means that electromagnetic radiation comes in clumps with a defined energy that gets bigger as the frequency of the light gets higher. ie Quanta
Why is there any connection between light and electromagnetism in the first place? what experiment shows that?
photons can affect electrons, how does that prove that photons are the mediators of electric force?
One of the first steps in the development of quantum mechanics was Max Planck's idea that a harmonic oscillator (classically, anything that wiggles like a mass bobbing on the end of an ideal spring) cannot have just any energy. Its possible energies come in a discrete set of equally spaced levels.An electromagnetic field wiggles in the same way when it possesses waves. Applying quantum mechanics to this oscillator reveals that it must also have discrete, evenly spaced energy levels. These energy levels are what we usually identify as different numbers of photons. The higher the energy level of a vibrational mode, the more photons there are. In this way, an electromagnetic wave acts as if it were made of particles. The electromagnetic field is a quantum field.Electromagnetic fields can do things other than vibration. For instance, the electric field produces an attractive or repulsive force between charged objects, which varies as the inverse square of distance. The force can change the momenta of the objects.Can this be understood in terms of photons as well? It turns out that, in a sense, it can. We can say that the particles exchange "virtual photons" which carry the transferred momentum. Here is a picture (a "Feynman diagram") of the exchange of one virtual photon. \ / \ <- p / >~~~ / ^ time / ~~~~ / | / ~~~< | / \ ---> space / \The lines on the left and right represent two charged particles, and the wavy line (jagged because of the limitations of ASCII) is a virtual photon, which transfers momentum from one to the other. The particle that emits the virtual photon loses momentum p in the recoil, and the other particle gets the momentum.This is a seemingly tidy explanation. Forces don't happen because of any sort of action at a distance, they happen because of virtual particles that spew out of things and hit other things, knocking them around. However, this is misleading. Virtual particles are really not just like classical bullets..........
Electrons can affect electrons, protons can affect electrons, does that make protons and electrons the mediators of electric force?You guys keep telling me about the photoelectric effect and how light is quantized, but that seems completely arbitrary to me, unless you can show that electromagnetism is quantized too.
How about I point out ways that photons act different from electric force, and ya'll can point out my errors.1.The fact that photons are only created in oscilating/accelerating charges seems completely arbitrary since oscillation and acceleration have nothing to do with electromagnetism/maxwells equations.
2.if photons mediate the electric force, that would mean that a photon would have to arrive at an object in order for it to experience electric force, as far as I know, no experiment shows that to be the case.
3.Photons can be blocked/redirected, as far as i know no experiment shows that to happen to electromagnetism.
4. Photons always push, electromagnetism pushes and pulls.
5. electromagnetism is greatest at right angles to motion, photons dont mainly emit themselves at right angles to motion.
6. electrons always seem to be the emitters of photons shouldnt an equal amount come frome protons, since electric force applies to both?
7. electric force drops in strength at the inverse square law, photons would obey that law if they were emitted in completely random directions, they arent ie lasers.
4. I didnt understand the explanation in that link at all. did you? What experiments show that that idea is valid. Explanations like that is what makes people not like quantum mechanics.
5. whats wrong with my statement? the fields are maximum perpendicular to the force, so shouldnt the amount of photons released be maximum perpendiular to the motion as well?
6. I dont see how your response is remotely related to my question.
7. What experiment shows that electric and magnetic fields don't decay at 1/r^2
8. All objects dont emit the same amount of photons, an oxygen atom on the surface of the sun emits a lot more than an oxygen atom at the north poll. Yet electric charge is always conserved.
9. What about static objects with charge, how do they emit photons?
Im just going to go over your rebuttals for all my points.1. You dont have to answer this question since it isnt a problem per se, I just find it odd that the creation of photons corresponds with something that is totally unrelated to electromagnetism.
2. a photon is the mediator of electric force and the only mediator, so you could say that the only way for an object to experience electric force is if the object absorbs a photon.
So if the titanic were to set sail and accelerate each one of its particles would have to absorb its very own photon, corresponding with the exact amount of energy required to accelerate it to that velocity. So if you ever found a particle that accelerated without absortion of a photon, not counting the other forces, that would violate the photon/electromagnetic connection.
3. okay your saying that if you put an object that is capable of blocking the photons that pass inbetween two charged objects, that it would also stop the net electric force between the two by creating an "anti field" of the exact opposite strength relative to the two(if it blocked all photons). This is the first real argument ive seen since its the only one that actually relates photons to electromagnetism. But I doubt that method actually works in every situation. I see a lot of potential problems with that idea. but ill just start with one. what if you put a great insulator, and an object that blocks a lot of photons in between it? Because in order for it to work, the blocking ability of the object would have to correspond exactly with the new induced field inside it.
7. What experiment shows that electric and magnetic fields dont decay at 1/r^2
Also while I was writing this I thought of a couple more problems I dont understand. And Ill add them to my orignal list.8. All objects dont emit the same amount of photons, an oxygen atom on the surface of the sun emits a lot more than an oxygen atom at the north poll. Yet electric charge is always conserved.
First off, I dont understand why you guys are all attacking me (outside of jp)
for asking supposedly elementary questions that could be explained by any electromagnetism textbook. Apparently asking questions is rubbish, right soul surfer?My questions represent that I dont understand how this works, you guys pretend like im trying to tear down the theory or make up new physics, im not. And even if I was I still wouldnt understand your rudeness. They are problems that I see in the theory that I dont know how to resolve, Im not saying that they cant be resolved, or that they are real "problems".Maybe im a really bad writer, since I never seem to get my point across, but let me point out to you why I am not accepting your logic to my question. Remember what my question is? What evidence shows that electromagnetism is mediated completely and only by the emission of photons. Observe the structure of my questions, all my questions start with my understanding of electromagnetism, and then my understanding of how photons are emitted, then I try to tie them together, but I find that when I do that they seem incompatible. Notice that I state something about electromagnetism AND something about photons. The question is about how to relate the two, so your answers should also be about relating the two, just like my questions do. You guys always only mention one side of the argument, and you assume that the answer is a given while you are answering. Does this make any sense to anyone?For example the photoelectric affect seems to be a popular choice to supposedly "answer" my question. This is an experiment that explains the nature of photons. Its not about the nature of electromagnetism, unless you assume that the answer to my question by saying "and since photons are the mediators of electromagnetism, electromagnetism is also quantized". You cant make that jump, IT IS MY QUESTION. That's about as usefull as telling me supercalifragilisticexpeolidoucious means supercalifragilisticexpeolidoucious. You cant assume the answer of the question while answering. Now please if you dont understand what I mean by this, just stop answering my questions, since you will only make me more frustrated.To lightarrow1. Where in electromagnetism does it say that acceleration affects the strength of charge?
3. Im just saying that if your theory of blockage works then the ability for an object to block photons from passing would have to correspond exactly with its reluctance to become polarized. does it?
5. Great you explained how electromagnetism affects the strength of charge perpendicular to the motion, I allready knew that, where is your connection then to quantum mechanics theory where it apparently says photons are emitted more in a perpendicular direction to motion?
6. Well if electrons are in better position to absorb photons, wouldnt that mean that electrons should have a stronger charge on average than protons?
7. Talking about groups of particles just complicates things, im talking about the individual, since macroscopic scales are just the products of the individual. There are ways to direct the emission of a photon, I dont know of a way to direct the field of electromagnetism, or at least not in the same way you would direct a photon.
8. I didnt mean that photons carry negative or positive charge, making other particles more or less charged. I meant that if you had an object with the same amount of charge, lets say two electrons. If one was in a position to absorb more photons than the other, it would push harder than the other(if photons are the carriers of electric force)
9. Charges affect each other wether they are accelerating or not.
Brain you are talking rubbish. go away and read some basic textbooks.The simple explanation is you get one hydrogen atom in a slightly excited state one of its electrons changes its orbit, loses some electromagnetic energy and emits a photon and nothing else. That is precisely how photons mediate the electromagnetic force ie every change of electromagnertic energy in every particle in a material invoves the emission and absorbtion of photons.