# Cosmic inflation

- kind: problem
- status: partial
- year: 1980
- authors: Alan Guth

**Statement.** Did the universe undergo a brief period of exponential expansion before the hot Big Bang?

Inflation explains why the universe is so flat and uniform, and its predictions for the spectrum of density fluctuations have been confirmed. Its signature in primordial gravitational waves, B-mode polarization, has not been seen. BICEP2 announced a detection in 2014 that turned out to be galactic dust.

Posed 1980, Alan Guth.

## Sources

- [Wikipedia: Inflation (cosmology)](https://en.wikipedia.org/wiki/Inflation_(cosmology))

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

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