I How to quantum mechanically describe the photon?

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This might sound stupid , but I am wondering how exactly could I describe the momentum eigenfunctions of photons?

EDIT:
to destroy ambiguity, I am searching for a quantum mechanic description of monochromatic light similar to how we represent it classically as:

E-> = a->cos(wt+phi)
 
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Somali_Physicist said:
This might sound stupid , but I am wondering how exactly could I describe the momentum eigenfunctions of photons?
##|p>## :biggrin:
 
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Demystifier said:
##|p>## :biggrin:
more precisely, ##|p\rangle##
 
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witty responses and as true as true can be. does it help our @Somali_Physicist ?
 
A quantum description of photons requires quantizing the electromagnetic field. This is discussed in any textbook on quantum field theory or quantum optics, and in many quantum-mechanics textbooks. This will result in operators that create and destroy photons with definite momentum and polarization. Acting on the vacuum (the state of no particles) with a single-photon creation operator produces a momentum eigenfunction. Acting with the exponential of a creation operator (with a specific coefficient) will create a "coherent state" of photons, all with the same momentum, which is as close as you can get to a classical field in the quantum theory.
 
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Avodyne said:
A quantum description of photons requires quantizing the electromagnetic field. This is discussed in any textbook on quantum field theory or quantum optics, and in many quantum-mechanics textbooks. This will result in operators that create and destroy photons with definite momentum and polarization. Acting on the vacuum (the state of no particles) with a single-photon creation operator produces a momentum eigenfunction. Acting with the exponential of a creation operator (with a specific coefficient) will create a "coherent state" of photons, all with the same momentum, which is as close as you can get to a classical field in the quantum theory.
Thank you
So there is no one liner equation ?

What is your textbook called
 
Somali_Physicist said:
This might sound stupid , but I am wondering how exactly could I describe the momentum eigenfunctions of photons?
Weinberg's "The Quantum Theory of Fields" Chapter 2 has a nice discussion of momentum eigenstates of various particle types.

Demystifier said:
##|p>## :biggrin:
A. Neumaier said:
more precisely, ##|p\rangle##
There should also be helicity right? ##|p,\sigma\rangle##
 
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DarMM said:
There should also be helicity right? ##|p,\sigma\rangle##
Or helicity left, ##|p, - \sigma\rangle ##
 
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Somali_Physicist said:
So there is no one liner equation
The relevant equation is that for the vector potential of the e/m field in Lorentz gauge.
 
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A. Neumaier said:
Or helicity left, ##|p, - \sigma\rangle ##
What's the difference between the left and and right side of the brain? On the right side there is nothing right, while on the left side there is nothing left.
 
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Demystifier said:
On the right side there is nothing right, while on the left side there is nothing left.

I prefer this: On the left side there is nothing right, while on the right side there is nothing left.
 
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Pony said:
I prefer this: On the left side there is nothing right, while on the right side there is nothing left.
It's not sufficiently paradoxical. A quantum description is not good if it does not look like a paradox. :biggrin:
 
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It's not even right since on the right hand the thumb is at the left...
 
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