I have read this question (in the comments):
Photons can be polarized which somehow affect their physical shape considering photons polarized parallel to a slit can make it through but do not make it through when polarized perpendicularly to the slit.
And this one:
That's why photons of microwave frequencies can't escape from the microwave, either. But the interpretation is different: the wave function isn't directly measurable like the electric fields. Instead, it encodes (after squaring) the probability density that the photon is here or there.
Now as far as I understand, photons are defined as elementary point particles in the Standard Model. I do understand that a large number of photons build up the classical EM waves in a very nice way.
Nowadays we do have single photon emitters, and if such a device emits a single photon towards a slit so that the photon is perpendicularly polarized (relative to the slit), then will the photon pass or not?
Now the image above explains the filter (polarizer) as where only parallel components get through, and perpendicularly polarized components do not get through.
I do not really understand this explanation in case of a single photon, since it is an elementary particle, and, even though it shows wave properties, it should not have parallel or perpendicular components (or constituents).
So basically, if a photon is an elementary particle, and does not have any components or constituents, then how can we state that it will not pass through the slit (if it is perpendicularly polarized)?
I do understand that slits can stop photons based on their wavelength, that is, for example in the case of a microwave mesh. But this example is not about wavelength, but polarization. How can a slit stop a photon just based on polarization, if the photon is elementary, and does not have for example vertical and horizontal components?
The last one says that single photons are described by the wavefunction, that isn't directly measurable like the EM fields (so it does not have vertical or horizontal components), but rather it describes the probability of finding the photon in space. But if the single photon is described by the wavefunction (and does not have vertical or horizontal components), then the slit should not be able to stop the photon based on polarization.
- Why can't a single photon pass through a slit if it is perpendicularly (relative to the slit) polarized?