Fermi Golden Rule

The Fermi Golden Rule is a principle in quantum physics that predicts the rate at which a system transitions from one energy state to another when disturbed, like by a small external influence. Imagine it as a way to estimate how quickly an atom or particle will change its energy level due to a tiny "push." It helps scientists understand processes like radioactive decay or how atoms absorb and emit light, by providing a mathematical way to calculate the likelihood and speed of these transitions happening over time.