- #1

MisterX

- 764

- 71

I am not understanding something from my textbook. This is related to Fermi's Golden rule. It's about what happens when the matrix element of the perturbation [itex]H'[/itex] ends up being a Dirac delta for chosen normalization. Here is Fermi's Golden rule.

[itex]\Gamma_{ba} = 2\pi \left|\langle b \mid H'\mid a \rangle \right|^2 \delta\left(\omega_a - \omega_b \right) [/itex]

I don't understand what is meant by "...is the decay rate into all the particles in the volume [itex]V[/itex]. The number of particles in [itex]V[/itex] is [itex]V/(2\pi)^3[/itex]."

[itex]\Gamma_{ba} = 2\pi \left|\langle b \mid H'\mid a \rangle \right|^2 \delta\left(\omega_a - \omega_b \right) [/itex]

I don't understand what is meant by "...is the decay rate into all the particles in the volume [itex]V[/itex]. The number of particles in [itex]V[/itex] is [itex]V/(2\pi)^3[/itex]."