Fermi's golden rule contains a term that is the density of the final states ##\rho(E_{final})##. For my problem we have no time depending potentials so that's the same as ##\rho(E_{initial})##.(adsbygoogle = window.adsbygoogle || []).push({});

If I understand the definition of ##\rho## correctly, it's the number of states in an interval ##[E_{f},E{f}+dE]## divided by ##dE## which just gives ##dN/dE##.

However... what if there are infinite different states in this interval?

Example:

A -> B + C + D

The final wavefunction will be a three particle wavefunction that will be able to distribute any final energy ##E_f## in an infinite number of ways among the different particles ##B,C,D##. This would mean that ##\rho## is infinite here.

What am I missing?

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Density of states in Fermi's golden rule

**Physics Forums | Science Articles, Homework Help, Discussion**