Collapse of the wave-function of a single photon in the general sense

entropy1
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non-locality and the collapse of the wave-function of a single photon

I'm a bit of a layman on english and on physics, so here it is.

My questions are about the collapse of the wave-function of a single photon in the general sense. I will mention where I mean to pose a question.

If we may consider a single photon-particle as a wave with corresponding wave-function... (may we? question 1)

...and if we consider the physical manifestation of the likely position of this particle in time as determined by this function as, ideally, a 'growing' sphere in diameter.. (may we? question 2)

...then may we consider the 'detection' of the particle as a collapse of the corresponding wave-function... (may we? question 3)

...thus prohibiting 'detection' of this particle on every place on the, now collapsing, sphere? (question 4)

Is this prohibition a so called 'non-local' effect? (question 5)

Is it possible to so 'instantly' transfer information of the 'detection' all over the sphere? (question 6)

I assumed that the meaning of 'detection', 'non-local' and 'instantly' were clear.
Questions 5 and 6 are the ones I'm really interrested in.

Thanks very much in advance! You will probably laugh about this one.
I really know nothing about this, but it troubles me...can't sleep.
 
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entropy1 said:
If we may consider a single photon-particle as a wave with corresponding wave-function... (may we? question 1)

No, because photons can NOT be described using a wavefunction (in the Schroedinger sense). There are all sorts of technical ways to try to get around this (mainly introducing other mathematical tools), but the fact remains that photons can not be described using wavefunctions in the same way as for example electrons.

Also, the wavefunction of a particle is not (neccesarily) "geometrical" in the sense that you describe.
 


f95toli said:
No, because photons can NOT be described using a wavefunction (in the Schroedinger sense). There are all sorts of technical ways to try to get around this (mainly introducing other mathematical tools), but the fact remains that photons can not be described using wavefunctions in the same way as for example electrons.
Thanks! I didn't know that! Could you tell me a littlebit about why photons can't be described by a wavefunction? And where can I find out more about that fact?
 
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unusualname said:
A discussion of some of the problems:

http://arxiv.org/abs/quant-ph/0508202

Wow! Very nice resource, unusualname! Thanks! :smile:
(can probably spend some nice reading-hours with that)
 
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f95toli said:
No, because photons can NOT be described using a wavefunction (in the Schroedinger sense). There are all sorts of technical ways to try to get around this (mainly introducing other mathematical tools), but the fact remains that photons can not be described using wavefunctions in the same way as for example electrons.

Also, the wavefunction of a particle is not (neccesarily) "geometrical" in the sense that you describe.

May I ask then what particles can be described using the wave function .e.e for a free particle, particle in a box, in a box with bump bottom and the harmonic oscillator?

Are these based on the electron?

Thanks
 
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