Timeline for How can energy of oscillators be quantised but they can still vibrate at all frequencies?
Current License: CC BY-SA 3.0
9 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Sep 11, 2017 at 19:54 | comment | added | user137289 | You can compare with phonons in a solid. At low T, the Debye model gives a Cv proportional to $T^3$, energy proportional to $T^4$, same as the Stefan-Boltzmann law. But in a crystal, there is a short-wavelength cutoff at the nearest-neighbor distance, which results in a constant Cv at high temperature. But EM waves can be arbitrarily short. | |
| Sep 11, 2017 at 18:02 | comment | added | QCrypt | and the fact that it is considered "black". Don't forget that it is a model, i.e. an idealized description. | |
| Sep 11, 2017 at 17:59 | comment | added | ModCon | This clears my question. But I would like to ask how is it that oscillators of all frequencies are contained? Is it the shape of the body? And thanks! | |
| Sep 11, 2017 at 17:58 | vote | accept | ModCon | ||
| Sep 11, 2017 at 17:51 | comment | added | QCrypt | "it has to contain oscillators at all possible frequencies because it is a blackbody" -> yes this is what i mean. | |
| Sep 11, 2017 at 17:50 | comment | added | ModCon | And it has to contain oscillators at all possible frequencies because it is a blackbody? Because intuitively it seems to me that the standing waves of a cavity may not capture all possible frequencies. Though I am using the classical picture of standing wave of strings to visualise this which may be wrong. | |
| Sep 11, 2017 at 17:47 | comment | added | QCrypt | well I meant that there is a single cavity containing oscillators at all possible frequencies. | |
| Sep 11, 2017 at 17:45 | comment | added | ModCon | So what you are saying is that although oscillators in a particular cavity are having discrete energy, there are many cavities and each of these may have different set of allowed frequencies, and so together all possible frequencies can be attained. And the fact that all of them do add up to capture all possible frequencies is because it is a blackbody which must absorb all radiation. Have I understood it correctly? | |
| Sep 11, 2017 at 17:16 | history | answered | QCrypt | CC BY-SA 3.0 |