A mathematical function that describes a particle's quantum state, varying in space and time.

The square of the absolute value of the wave function (|Ψ|²), representing the probability of finding a particle at a specific point.

The wavelength (λ = h/p) associated with a particle's momentum (p), connecting its wave-like behavior.

The time it takes for half of a radioactive sample to decay.

The process where an atom absorbs a photon of the correct energy to jump to a higher energy level.

The process where an atom in an excited state spontaneously drops to a lower energy level, emitting a photon.

The process where an incoming photon triggers an excited atom to drop to a lower energy level, emitting an identical photon.

Spontaneous Emission: An atom emits a photon randomly. Stimulated Emission: An incoming photon triggers an atom to emit an identical photon.

Absorption: Atom gains energy, electron jumps to higher level. Emission: Atom loses energy, electron drops to lower level.

Points of zero displacement in a standing wave.

Points of maximum displacement in a standing wave.