[n] - (physics) an abrupt transition of an electron or atom or molecule from one quantum state to another with the emission or absorption of a quantum
noun (physics) an abrupt transition of an electron or atom or molecule from one quantum state to another with the emission or absorption of a quantum
an abrupt transition of a system described by quantum mechanics from one of its discrete states to another, as the fall of an electron in an atom to an orbit of lower energy. · any sudden and significant change, advance, or increase. Also called