- #1
Jano L.
Gold Member
- 1,333
- 75
Imagine light of frequency [itex]\Omega[/itex] enters a liquid and propagates in the z direction. Its velocity is reduced to c/n. This leads to reduction of its wavelength to 1/n of the vacuum wavelength and the wave is described by the macroscopic electric field
[tex]
\mathbf E (\mathbf x,t) = \mathbf E_0 \cos(\Omega t - n\Omega/c z).
[/tex]
However, does the reduction of the wavelength and speed occur also at the microscopic level?
Take one molecule of the liquid; it is surrounded by empty space, and is under action of the microscopic electromagnetic field. How would you describe this microscopic field, as a slowed-down wave
[tex]
\mathbf e (\mathbf x,t) = \mathbf e_0 \cos(\Omega t - n\Omega/c z).
[/tex]
or as a vacuum wave
[tex]
\mathbf e (\mathbf x,t) = \mathbf e_0 \cos(\Omega t - \Omega/c z).
[/tex]
or neither?
[tex]
\mathbf E (\mathbf x,t) = \mathbf E_0 \cos(\Omega t - n\Omega/c z).
[/tex]
However, does the reduction of the wavelength and speed occur also at the microscopic level?
Take one molecule of the liquid; it is surrounded by empty space, and is under action of the microscopic electromagnetic field. How would you describe this microscopic field, as a slowed-down wave
[tex]
\mathbf e (\mathbf x,t) = \mathbf e_0 \cos(\Omega t - n\Omega/c z).
[/tex]
or as a vacuum wave
[tex]
\mathbf e (\mathbf x,t) = \mathbf e_0 \cos(\Omega t - \Omega/c z).
[/tex]
or neither?