1
vote
2answers
37 views

optical diffusion (scattering) versus refraction

When an electromagnetic wave meets an interface a part of it is reflected and part of it is refracted (and from the refractive index I can calculate the angles of propagation and the intensities using ...
7
votes
1answer
152 views

Does QED provide a closed form for Coulomb logarithms?

The classical models for the integrand as well as the cut-offs in computing the Coulomb logarithm are pretty rough. Does quantum electrodynamics have definite expressions for the quantity ...
2
votes
1answer
52 views

Must neutron speed and diffusion speed be comparable for neutron scattering experiments to be probe atomic diffusion?

Neutron scattering experiments are sometimes used to study atomic diffusion in solid materials. My intuition is that the typical speeds of the atoms diffusing in the material--say, the diffusion ...