Timeline for Free electron laser has really free electrons?
Current License: CC BY-SA 4.0
4 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Apr 14, 2019 at 22:52 | vote | accept | Árpád Szendrei | ||
| Apr 14, 2019 at 19:13 | comment | added | Emilio Pisanty | "the magnetic field has a timelike four momentum" - no. The magnetic field mediates the transfer of momentum between the electrons and the magnet, which has a timelike four-momentum. The virtual-photon picture has its uses, but it's prone to leading down all sorts of wrong alleys (many of which you seem to be taking). | |
| Apr 14, 2019 at 17:47 | comment | added | Árpád Szendrei | thank you so much! so the electrons do not need to be bound to an atomic system. they just need to interact with the magnetic field via virtual photons right? that is where they gain the kinetic energy from to accelerate, thus making them able to emit photons. So when they emit the photons, they lose kinetic energy, but they gain kinetic energy from the magnetic field's virtual photons. the magnetic field has a timelike four momentum, and so the electrons can exchange momentum and energy with it when emitting a photon? | |
| Apr 14, 2019 at 17:45 | history | answered | Emilio Pisanty | CC BY-SA 4.0 |