Unusual bound or localized states
نویسندگان
چکیده
We summarize unusual bound or localized states in quantum mechanics. Our guide through these intriguing phenomena is the classical physics of the upside–down pendulum, taking advantage of the analogy between the corresponding Newton’s equation of motion and the time independent Schrödinger equation. We discuss the zero–energy ground state in a three–dimensional, spatially oscillating, potential. Moreover, we focus on the effect of the attractive quantum anti–centrifugal potential that only occurs in a two–dimensional situation.
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