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After much research... the concept is correct, although 'absorbed' and 'retransmitted' are not the right words to use. http://en.wikipedia.org/wiki/Slow_light

"Light traveling within a medium is no longer a disturbance solely of the electromagnetic field, but rather a disturbance of the field and the positions and velocities of the charged particles (electrons) within the material. The motion of the electrons is determined by the field (due to the Lorentz force) but the field is determined by the positions and velocities of the electrons (due to Gauss' law and Ampere's law). The behavior of a disturbance of this combined electromagnetic-charge density field (i.e. light) is still determined by Maxwell's equations, but the solutions are complicated due to the intimate link between the medium and the field. Understanding the behavior of light in a material is simplified by limiting the types of disturbances studied to sinusoidal functions of time. For these types of disturbances Maxwell's equations transform into algebraic equations and are easily solved. These special disturbances propagate through a material at a speed slower than c called the phase velocity."

As another commented pointed out, you're splitting hairs. The "speed" of light and how fast it is "moving" depends on how you define those terms. The second paragraph of the wikipedia speed of light article has it right "The speed at which light propagates through transparent materials" - which does change.



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