Question

In quantum physics, Fermi's golden rule, also known as the golden rule of time-dependent perturbation theory, is a formula that can be used to calculate the rate at which an initial quantum state transitions into a final state?

Answer 1

Yes, that's correct! Fermi's golden rule is a fundamental result in quantum physics that allows us to calculate the transition rate between quantum states in the context of time-dependent perturbation theory. It provides a way to determine the probability per unit time for a quantum system to make a transition from an initial state to a final state when the system is subjected to a weak perturbation.

The golden rule is typically expressed in the following form:

$W_{i\to f}=\frac{2\pi }{\hslash }|V_{fi}{|}^2\rho (E_i)$

where $W_{i\to f}$ represents the transition rate from an initial state $i$ to a final state $f$, $V_{fi}$ is the matrix element of the perturbation between the initial and final states, $\rho (E_i)$ is the density of states at the initial energy $E_i$, and $\hslash$ is the reduced Planck's constant.

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