What is the physical meaning of a single photon's frequency?     When the fields cross zero, is there less probability of finding an photon there? What does the amplitude of the waves represent, if anything?   And if the frequency has to do with probability, how to interpret circularly polarized light where there's no point that the magnetic and electric fields are both zero?
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At the end of this nice video (), she says that  is a chain reaction of electric and magnetic fields creating each other so the chain of wave moves forward.  I wonder where the  is in this explanation. What is the relation between electromagnetic wave and photon?
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I was wondering (since I've looked pretty hard and haven't been able to find anything)-  are there any models that explain the polarization of light upon reflection? Everywhere I've looked I've seen things like the Brewster angle mentioned, and empirical data, but I haven't yet found any theoretical models that explain this type of polarization. Can anybody point me in the right direction? Or have no such models been made?
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Somebody mentioned on Freenode chatroom for physics that All  are delivered in form of Photons not just light.   Is it true? Does that mean if we get a THF electrical oscillator to emit the frequencies that are visible to the eye, do we see light coming out of the circuit?
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$E = h\nu$ and $P = h\nu/c$ in vacuum. If a photon enters water, its frequency $\nu$ doesn't change. What are its energy and momentum: $h\nu$ and $h\nu/c$ ? Since part of its energy and momentum have been transferred to water, it should be less.  If water's refractive index is $n$, are the energy and momentum equal to $h\nu/n$ and $h\nu/c/n$ ?
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Is it theoretically possible to have a photon of any energy/wavelength? I have a vague memory in my mind of something like there being a minimum energy level for a photon and then the possible energy levels jump up in discrete but ever decreasing amounts, so that near e.g. the visible spectrum photon energies are for practical purposes continuous.
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Yesterday I read that we can affect the path and the 'form' (particle or wave) of a photon after the fact ().  Part of what is puzzling me is the beam-splitter. Are the individual photons actually being split into two new photons of lesser energy?  This  implies that you cannot split a photon but it seems that beam splitters do exactly that.
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When light (photon) is reflected the the original photon is absorbed by an electron and then emitted again. Does this "new" photon have the same wavelength, frequency etc. as the original?
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In basic quantum mechanics courses, one describes the evolution of quantum mechanics chronologically. Interference experiments with particles showed that particles should have a wave character; on the other hand, the photo-electric effect showed that electromagnetic waves should have a particle character. So there's a particle-wave duality.  The course continues with postulating the Schrödinger equation, and solves the problems for the wave character of classical particles (e.g. with respect to harmonic oscillators to solve the UV-catastrophe in the description of blackbody radiation). On the other hand, one describes the photo-electric effect extensively with perturbation theory, as the electromagnetic wave acts as a periodical force on an electron. But the electromagnetic wave is still described with the Maxwell equations, and not by Schrödinger.  Suppose history went a little differently: the corpuscular character would still be the generally accepted behaviour of light (as Newton preferred), and one discovered the wave character of photons and electrons simultaneously by doing interference experiments. The laws of Maxwell, Gauss, Faraday and Ampère weren't discovered yet. Schrödinger comes up with his equation, and one describes the wave character of electrons as well as photons with this equation.   Would this equation give a exhaustive description of the electromagnetic (and vector like) behaviour of photons? In other words: is the Schrödinger theory, in some way, equivalent to the Maxwell theory for the description of photons? Or are the Maxwell equations some kind of limit for greater dimensions (like the Newton equations for mechanics)? What is the link between these two "wave character" descriptions of photons?
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Essentially this question boils down to "why does the energy of light depend on frequency?".    The analogy my textbook (pg. 272 principles of chemistry A molecular Approach 3rd edition by Nivaldo J. Tro) gave was that photons with higher frequency are like baseballs, whereas photons with lower frequency are like ping pong balls. Meaning that each photon has higher energy.  This StackExchange page () seems to say the opposite, that the energy of each photon is the same and what changes is the amount of photons per area.
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This asked:   And also this:     The second question is contradictory; maximum frequency -> minimum wavelength.   I am asking the very opposite;    What is the minimum frequency and maximum wavelenght of electromagnetic radiation?   The lowest measured/defined seems to be 3 Hz;  Which means a wavelenght 1/3 of the speed of light; ~100 000 000 m.   But this can't be the physical limit for the wavelenght. Does such a physical limit for the wavelength exist? (Similar limit like the speed of light is for velocity).
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Since electromagnetic energy is carried by photons and moves in forms of waves, does it mean that a single photon when propagating through space doesn't follow the straight path but instead always moves up and down, up and down like a wave. If so another question arises the speed of propagation of light in vacuum is fixed meaning that it will always take the same amount of time for it to travel from point A to point B, but if a photon always moves up and down it will also mean that it travels longer distance than the distance between A and B and so it ill travel faster than light propagates, is it even possible, could you please clarify these concepts for me?
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I continue to find it amazing that something as “bulky” and macroscopic as a static magnetic or electric field is actually a manifestation of virtual photons.  So putting on your QFT spectacles, look closely at the space near the pole of a powerful magnet – virtual photons! Now look between the plates of a charged capacitor – virtual photons again!   But if it’s all virtual photons, how do we get the difference between a magnetic and electric field?  [This question needs the tag "magnetostatics" as well].
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To be clear here, My question arises from studying Electromagnetic induction and polarisation and photoelectric effect. From here I've gained the knowledge that creation of a photon involves:  Electromagnetic Induction - The fact that a time varying spatial magnetic field which creates a closed loop electric field [Super Confusing as to why universe does that] Polarisation - In the books, they show that light is oscillating electric field vectors and magnetic field vectors Photoelectric Effect - Creation of light has something to do with an electron returning to a lower energy state, not saying that it's the only way.  So how does light get produced? I'm seeking in-depth explanation.  Some Context The question arose when I was talking to my friend about a hypothesis of mine where I was saying that If I released a photon from , say a torch. I could, under some known error margin, say at what instant the photon was created but according to what I've heard multiple times, time stops at light speed. So, any photon at 'c' would basically never had experienced any time. So, from the perspective of the photon, its birth can't be defined. We seem to reach a paradox here, if I observe a time at which the photon was created but the photon has no notion of time, it has no notion of a beginning or an end. Then, I tried to expand the concept of the hypothesis to say that maybe in a similar sense, the universe doesn't hold a concept of beginning or an end. As we experience it's perspective, we can't determine its birth time using our maths which has been cultivate throughout this universe, and we also know that maths do break down when we try to solve equations for the t=0 time of Big Bang. NOTE: This talk was just to have fun, I just like physics and like to talk about the universe, however, I understand that I might have just annoyed someone by ignoring a dozen of laws and theorems that I'm yet to find out about. APOLOGIZES!  I'm expecting a somewhat dumbed down explaination, now don't get too carried away by that. I'm a high school student but I do love a bit of technical mumbo jumbo but I'm just asking to keep in mind that I'm in high school. Example: Say we have an equation: x3+x2-x+44=0 Instead of saying the degree of equation is 3 maybe say the highest power in the equation is 3.
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This was discussed in an answer to a  but I think that it deserves a separate and, hopefully, more clear answer.  Consider a single photon ($\lambda$=532 nm) traveling through a plate of perfect glass with a refractive index $n=1.5$. We know that it does not change its direction or other characteristics in any particular way and propagating 1 cm through such glass is equivalent to 1.5 cm of vacuum. Apparently, the photon interacts with glass, but what is the physical nature of this interaction?  Let's not consider high-order effects like Rayleigh/Raman scattering.
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The electromagnet spectrum looks to be continuous, yet energy is discrete. Shouldn't one see evidence of the electron's "quantum leap"? What's going on?     Moderator, please size my photo. Thank you.
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I sometimes hear statements like:     Quantum-mechanically, an interference pattern occurs due to quantum interference of the wavefunction of a photon. The wavefunction of a single photon only interferes with itself. Different photons (for example from different atoms) do not interfere.   First of all -- is this correct?   If it is correct -- how do we explain basic classical interference, when we don't care about where the plane waves came from?   I heard that there are experiments with interference of two different lasers -- is this considered as a refutation of the statement? If it is -- how should one formally describe such a process of interference of different photons?  Finally -- such statements are usually attributed to Dirac. Did Dirac really say something like that?
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Why do we say that electromagnetic wave is oscillating? Or does light propagate really in a wavy form like this image?    What is making the photons oscillate and how is it oscillating is it oscillating back and forth (and if oscillating back and forth how does it move if its moving back and forth at the same point?)?  Why do we say that the EM field is constantly changing when in the above picture its constant? (we know that a compass is not able to follow an electromagnetic radiation because the EM field is constantly changing)