# Wien's distribution law

From AMS Glossary

## Wien's distribution law

A relation, derived on purely thermodynamic reasoning by Wien, between the monochromatic emittance of an ideal blackbody and that body's temperature.

*e*

_{λ}is the monochromatic emittance (emissive power) of a blackbody at wavelength λ and absolute temperature

*T*, and

*f*(λ

*T*) a function that cannot be determined purely on classical thermodynamic grounds. The specification of

*f*(λ

*T*) by Planck in 1901 formed the beginning of modern quantum theory.

*Compare*Wien's law.