- Please Solve With Proper Orientation 1 (78.19 KiB) Viewed 42 times
please solve with proper orientation.
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answerhappygod
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please solve with proper orientation.
please solve with proper orientation.
4.5 Consider an atom in a cavity containing black-body radiation. When the atom is in a state a with energy E, there is a probability per unit time that it will make a transition to a state h with energy E< E, emitting a photon of frequency w = (E- Eh)/h in a state k. Denote this probability per unit time by P[(a, nk) → (b, nk+1)] when there are already k photons in state k, and the probability per unit time for the reverse process of absorption by Pl(b, nk)→→ (a. n 1)]. From quantum electrodynamics (QED), one can deduce (roughly speaking) that Pl(a, nk)→ (b, nk + 1k)] = (nk + 1)P[(a, 0k) → (b. lk)| Pl(b, nk) → → (a, n-1)] = nk Pl(b, 1k) → (a, Ok)I. (a) Use the condition of detailed balance for thermal equilibrium and the above results of QED to derive Planck's law of black-body radiation. (b) Assume that Planck's law and the condition of detailed balance are valid. From these assumptions, is it possible to show that the above relations ought to be true in QED? If not, what further information is needed?
4.5 Consider an atom in a cavity containing black-body radiation. When the atom is in a state a with energy E, there is a probability per unit time that it will make a transition to a state h with energy E< E, emitting a photon of frequency w = (E- Eh)/h in a state k. Denote this probability per unit time by P[(a, nk) → (b, nk+1)] when there are already k photons in state k, and the probability per unit time for the reverse process of absorption by Pl(b, nk)→→ (a. n 1)]. From quantum electrodynamics (QED), one can deduce (roughly speaking) that Pl(a, nk)→ (b, nk + 1k)] = (nk + 1)P[(a, 0k) → (b. lk)| Pl(b, nk) → → (a, n-1)] = nk Pl(b, 1k) → (a, Ok)I. (a) Use the condition of detailed balance for thermal equilibrium and the above results of QED to derive Planck's law of black-body radiation. (b) Assume that Planck's law and the condition of detailed balance are valid. From these assumptions, is it possible to show that the above relations ought to be true in QED? If not, what further information is needed?