Does the speed of light actually slow down in glass?

AI Thread Summary
The discussion centers on the concept of light speed in different mediums, specifically whether light actually slows down in glass or if it remains constant while interacting with molecules. It is clarified that photons are absorbed and reemitted by the material, causing a delay that results in the perception of a lower speed. The speed of light in a vacuum is constant at approximately 3x10^8 m/s, but the effective speed in glass is slower due to these interactions. Participants express a desire for further resources to understand this phenomenon better. The topic highlights the distinction between the inherent speed of light and its effective speed in various materials.
buddingscientist
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ok I've been wondering about this for awhile

when people say the speed of light slows down when going through an object (ie glass).

does the speed of light actually slow down to 2x10^8 m/s

or does the speed of light actually stay constant at 3x10^8, but the photons collide with the SiO molecules in the glass (or whatever), such that by the time the photons exit the glass, it will have taken 1.5x longer than another photon that totally bypassed the glass and traveled in a straight line


i hope that general question I am asking is clear, thanks
 
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In materials photons are adsorbed and reemitted, this causes the delay which we interpret as a lower speed of light.
 
ahh right.
do you happen to know any websites that explain this?
this is beyong the scope of our syllabus
 
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