Quantum mechanics ================= *Quantum mechanics* is a fundamental theory that describes the behavior of nature at and below the scale of atoms and deals with the behavior of matter and light on the atomic and subatomic scale. .. py:currentmodule:: symplyphysics.laws.quantum_mechanics **Contents:** .. toctree:: :maxdepth: 4 laws.quantum_mechanics.harmonic_oscillator laws.quantum_mechanics.schrodinger laws.quantum_mechanics.expectation_value_of_observable laws.quantum_mechanics.probability_density_of_quantum_state