# Big Bang or steady state

- kind: problem
- status: solved (evidence tier V3)
- year: 1948

**Statement.** Did the universe have a hot, dense beginning, or has it always looked the same?

Two radio engineers traced a persistent hiss in their antenna to a uniform glow from every direction. It was the leftover heat of the early universe that Big Bang models predicted, and steady-state theory could not explain it. They first suspected pigeon droppings in the antenna.

*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.*

Closed 1965, Penzias and Wilson detect the cosmic microwave background.

## Sources

- [Wikipedia: Cosmic microwave background](https://en.wikipedia.org/wiki/Cosmic_microwave_background)

[Origins of the universe](/wiki/Space:origins.md) · [Cosmos](/wiki/Continent:cosmos.md)

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