# The ultraviolet catastrophe

- kind: problem
- status: solved (evidence tier V3)
- year: 1900
- authors: the Rayleigh–Jeans law

**Statement.** Why does a hot body not radiate infinite energy at short wavelengths, as classical physics predicts?

Planck fitted the measured blackbody spectrum by assuming energy is exchanged in discrete amounts, an assumption he regarded as a mathematical trick. Einstein took it literally in 1905 to explain the photoelectric effect. A mismatch between theory and a curve on a graph started quantum mechanics.

*Evidence tier V3 is the import default for a result the curation records as settled in the published record. No formal proof or certificate is attached to this page yet.*

Posed 1900, the Rayleigh–Jeans law. Closed 1900, Max Planck's quantum hypothesis.

## Sources

- [Wikipedia: Ultraviolet catastrophe](https://en.wikipedia.org/wiki/Ultraviolet_catastrophe)

[Quantum foundations](/wiki/Space:quantum-foundations.md) · [Physics](/wiki/Continent:physics.md)

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