Quantum mechanics

1. Dec 8, 2005

sweetvirgogirl

Charges of +q and -q are separated by a distance L.

What would be a typical energy of a virtual photon they exchange?

2. Dec 9, 2005

emptymaximum

what have you done so far?

why would they exchange a virtual photon in the first place?

3. Dec 9, 2005

dextercioby

Why do you mix photons with "distance L" ...?

Daniel.

4. Dec 9, 2005

sweetvirgogirl

I stated the problem as it is given in the book

5. Dec 9, 2005

dextercioby

Well, virtual photons are terms used in QED, but "distance L" between 2 pointlike charges has to do with classical electrodynamics, i.e. electrostatics...Do you see anything suspicious...?

Daniel.

6. Dec 9, 2005

emptymaximum

draw the feynman diagram. do conservation of momentum.
treat it like a collision.

7. Dec 9, 2005

bump

8. Dec 9, 2005

El Hombre Invisible

Can you not just use the time version of the uncertainty principal to determine the energy of the virtual photon? You can express $$\Delta t$$ in terms of L and c and find $$\Delta E$$.