Melt a Perfect Mirror: Atomic Mechanisms of Reflection

AI Thread Summary
The discussion centers on the atomic mechanisms behind the reflection of light from a perfect mirror, questioning whether absorption and re-emission of photons are necessary for reflection. It explains that reflection occurs when electrons in the material respond to electromagnetic fields, effectively canceling them and reradiating light out of phase, resulting in reflection. A perfect mirror cannot exist at finite temperatures due to the requirement of thermal equilibrium, which involves equal rates of absorption and emission of radiation. The conversation also touches on the possibility of melting a perfect mirror through radiative means, emphasizing the complexities of light interaction at the atomic level. Understanding these mechanisms is crucial for exploring the theoretical limits of perfect mirrors.
mezarashi
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Is it possible to melt a perfect mirror by radiative means? (reflects light of all frequencies with no absorption)

Which leads me to ask. What is the mechanism (at the atomic level), for the reflection of light? I've never had a satisfactory answer on the mechanism of reflection. Is it necessary for the atoms to firstly absorb the incoming photon, and then re-emit it? If so, what makes it make sure that the re-emitted light is identical to the incoming?
 
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Such a mirror cannot exist at finite temperature since it could not possibly come into thermal equilibrium with its environment, i.e. a temperature gradient would have to exist without the flow of heat. Thermal equilibrium requires both emission and absorption of radiation and they occur equally in order to equilibrate.

Reflection from the surface of a mirror (metallic, e.g.) occurs as a result of electrons responding to the applied electromagnetic field in such a way that they exclude electric fields within the material. Accelerated charges radiate so that, in effect, they cancel the applied fields by reradiating EM fields out of phase with the applied fields within the material. The reradiated field outside the material is what we call the reflected wave.
 
Last edited:
mezarashi said:
Is it possible to melt a perfect mirror by radiative means? (reflects light of all frequencies with no absorption)
Which leads me to ask. What is the mechanism (at the atomic level), for the reflection of light? I've never had a satisfactory answer on the mechanism of reflection. Is it necessary for the atoms to firstly absorb the incoming photon, and then re-emit it? If so, what makes it make sure that the re-emitted light is identical to the incoming?

There have been several threads discussing such issue. You may look at one of them here...

https://www.physicsforums.com/showt...+reflection+transmission+conduction+electrons

Zz.
 
Sorry about that. The title of the thread was not immediately suggestive of the discussed contents. Thanks for the response and link.
 
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