All Questions
6 questions with no upvoted or accepted answers
2
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Can one derive Planck's law by considering a more "natural" setting?
I have been wondering about this for a while. I've recently become a bit dubious regarding the usual derivation cited in textbooks of Planck's law (and its inaccurate predecessor, the Rayleigh-Jeans ...
- 20.8k
1
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Why is a cavity with discrete modes necessary in the derivation of Planck's law?
In my readings, I have come across the concept that a finite cavity allows for the quantization of electromagnetic modes, leading to discrete energy levels. However, it's not clear to me why this step ...
1
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0
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Information loss problem if almost perfect black body
Assume a almost perfect black body at temperature zero and consider pointing a signal, let's say a laser beam (pure state), on this body. What happens with the information of the beam?
My thoughts go ...
- 173
1
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probability of emission vs absorption in thermal radiation
I am trying to make sense of the thermal radiation emitted by a gas.
The radiative transfer equation is $$\frac{dI}{dx} = \epsilon - \kappa I,$$ where I is the intensity, $\epsilon$ is the ...
- 323
1
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Transitions coupled to different baths in quantum thermodynamics
I don't understand the general assumptions made during the separation of a single environment of the open system represented by the energy levels into two baths at two temperatures in the diagram ...
- 223
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What is the meaning of "radiative distribution of entropy"?
I was reading about black body radiation on Wikipedia. In the explanation section, it says:
"All normal (baryonic) matter emits electromagnetic radiation when it
has a temperature above absolute ...
