Physics:Quantum black-body radiation
Black-body radiation is the electromagnetic radiation emitted by an idealized object that absorbs and emits radiation perfectly. Classical physics predicted an ultraviolet catastrophe, with unlimited energy at high frequencies, but this contradicted experiment. Planck resolved the problem by assuming that radiation energy is exchanged in discrete units, introducing the quantum idea that helped launch modern quantum theory.
Classical problem
Classical descriptions of thermal radiation failed at high frequencies because they predicted too much emitted energy. This mismatch between theory and experiment became one of the key problems that led to quantum mechanics.
Planck quantization
Planck's solution assumed that matter and radiation exchange energy in discrete amounts. This idea is an early form of quantization and connects black-body radiation to the origin of the quantum concept.
Energy-frequency relation
The energy carried by each quantum is proportional to frequency, with the proportionality set by the Planck constant. This relation is also central to photons and electromagnetic radiation.
Ultraviolet catastrophe
The ultraviolet catastrophe names the classical prediction that the emitted energy should grow without bound at short wavelengths. Quantum energy packets remove this divergence and produce the observed spectrum.
Role in quantum theory
Black-body radiation is one of the historical foundations of quantum theory. It links thermal physics, radiation, and the discrete structure of energy exchange.
See also
Table of contents (198 articles)
Index
Full contents
References
Source attribution: Physics:Quantum black-body radiation