(physics) all the lines in the emission or absorption spectrum of hydrogen; each one corresponding to an allowed transition between quantum energy levels

(physics) The distribution of the intensity of particles or radiation emitted in a nuclear process as a function of energy - a unique signature of each process.

(quantum mechanics) A concept relating to energy spectra. Let H be the one-dimensional Schrödinger equation operator H=-(d²)/(dx²)+U_𝛼, where U_α is a periodic function of period α. The Bloch spectrum of H is the set of values E for which all the solutions of (H − E)φ = 0 are bounded on the whole real axis.

(physics) The characteristic pattern of dark lines or bands that occurs when electromagnetic radiation is passed through an absorbing medium into a spectroscope.

The range of conditions classified as pervasive developmental disorders, generally held to include autistic disorder, Asperger syndrome, and pervasive developmental disorder - not otherwise specified (PDD-NOS). Also includes childhood disintegrative disorder and Rett syndrome.

Synonym of autism spectrum

plural of political spectrum

The various political viewpoints represented as a continuum, ranging from the extreme left to the extreme right.

plural of optical spectrum

plural of light spectrum