Can photons and electrons have the same physical size?

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lightarrow said:
Infact, when you talk about emission and absorption, you are not talking about a photon during propagation, so, it's in those processes that the photon's size is zero.
AFAIK,the corresponding wavefunction must be employed to describe photon propagation.
Unfortunatelly ,it can't be visualized .It is constructed on abstract math space -not a real space.Probability waves can't be visualized for the same reason-they are not real.

To illustrate and make you furtherly wonder about difficulty of defining "size" of photon ,and that it can't be associated with wavelength,I would like to turn your attention to a very known and useful phenomenon..
Polarized EM wave.Ever heard of it?
Both ,from the standpoint of EM theory and experience a polarized EM wave can pass through a very thin slit which is perpendicular to its direction of polarization (if the slit is long enough).
Regardless of the wavelength, EM wave can be treated like a planar wave.

So the next question you may ask is how "thin" are the photons of such wave during propagation through the slit?And I will not be answering this one
:smile:
 
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tehno said:
AFAIK,the corresponding wavefunction must be employed to describe photon propagation.
Unfortunatelly ,it can't be visualized .It is constructed on abstract math space -not a real space.Probability waves can't be visualized for the same reason-they are not real.

To illustrate and make you furtherly wonder about difficulty of defining "size" of photon ,and that it can't be associated with wavelength,I would like to turn your attention to a very known and useful phenomenon..
Polarized EM wave.Ever heard of it?
Both ,from the standpoint of EM theory and experience a polarized EM wave can pass through a very thin slit which is perpendicular to its direction of polarization (if the slit is long enough).
Regardless of the wavelength, EM wave can be treated like a planar wave.
And what is strange in this? Polarization refers to field's intensity along specific directions, not to the presence or absence of the field along the slit. Infact, in the case, e.g. of a plane wave, the fields are still present along all the screen where the slit is made, polarization or not. I'm certainly not the one who visualize an EM wave as that line drawed on the books!

However, I started from a bit far away, asking about a photon's size, because I didn't want to ask at once what Really a photon is.
 
lightarrow said:
However, I started from a bit far away, asking about a photon's size, because I didn't want to ask at once what Really a photon is.
Then what kind of "size" you wanted to discuss about ?I thought you were referring to 3-dimensional world we are used to observe and size =spatial dimensions?:confused:
As shown by examples term "photon size" doesn't make sense if that was what was meant.
However,"what Really photon is ?" is a superdifficult question.
Nobody ,except God (maybe) ,can answer that one!
 
tehno said:
Then what kind of "size" you wanted to discuss about ?I thought you were referring to 3-dimensional world we are used to observe and size =spatial dimensions?:confused:
As shown by examples term "photon size" doesn't make sense if that was what was meant.
However,"what Really photon is ?" is a superdifficult question.
Nobody ,except God (maybe) ,can answer that one!
What I mean is that I wanted to discuss about a "photon's size" first, to understand better if my doubts about "what a photon is" were reasonable.