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Is refraction of light a thermodynamic process?

Can it be explained by conservation of energy?

If so, does temperature has an effect on refraction of light?

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    $\begingroup$ No. Yes. To a first approximation, no. Seriously, it is a electromagnetic process and well explained by electromagnetism. Why do you think it needs explaining further? $\endgroup$ – dmckee May 3 '15 at 21:38
  • $\begingroup$ What causes light to loose it's speed inside a different medium? Then as refraction is explained by classical methods there should be conservation of energy involved there.. $\endgroup$ – slhulk May 3 '15 at 21:56
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    $\begingroup$ All phenomenas in nature must follow thermodynanics ,but that doesnt mean you can explain phenomenas with only thermodynamics. $\endgroup$ – Paul May 4 '15 at 2:58
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    $\begingroup$ Total internal reflection has a thermodynamic/statistical interpretation: is a mismatch between the plentiful internal optical modes and the fewer modes available in the less optically dense material across the interface. I have not thought about a similar analogue for refraction but I imagine the same mental model could be used to describe this process. $\endgroup$ – boyfarrell May 4 '15 at 8:08
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    $\begingroup$ I would echo @Paul 's point, but you may also be interested in the concept of etendue, which relates refraction from a general surface (such as a lens) to thermodynamic principles: physics.stackexchange.com/questions/234996/… $\endgroup$ – Rococo Aug 29 '16 at 19:40
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Refraction of Light is not a Thermodynamic process. If you study the QED basis of refraction, you notice that the difference happens in time. The speed of light is constant, and a photon which is refracted, doesn't actually travel any slower, it just travels a longer path, and needs thus more time. If it hit's somewhere, then it's not refracted. It's gone, and this increases heat. But that was not the photon which got refracted. And this heat might cause a thermal expansion on the material, which means the refracting properties of the material are changing. Still, this change is NOT caused by the refracted photons. It's caused by the absorbed photons.

Conclution;

  • No, It's not a thermodynamic process.
  • No, But it can be explained through time.
  • Yes, Temperature has an effect to refrection through thermalexpansion, but this change is not caused by refraction. It's caused by the absorption.
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  • $\begingroup$ I like this particle based derivation. $\endgroup$ – Bill Alsept Oct 2 '16 at 19:49

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