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Inflation
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Rapid exponential expansion in the early universe.
A proposed exponential expansion at 10⁻³⁶ to 10⁻³² s that solved the horizon and flatness problems and generated density seeds from quantum fluctuations.
Expanded by a factor ≥ 10²⁶.
Gravitational-wave imprints sought in the CMB.
In more detail
Cosmic inflation is a brief period of exponential expansion in the very early universe, which explains the flatness, uniformity and absence of monopoles. It also seeded the structures we see today.
Real-world uses
- Inflation explains the observed uniformity of the CMB.
- Predictions of inflation are tested with CMB polarisation.
- Cosmologists use inflation to explain why the universe is so flat and uniform on large scales.
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Frequently asked questions
What drove inflation?
A hypothetical field called the inflaton, whose nature is not confirmed.
Why is it important?
It solves several puzzles of the standard Big Bang model.
What was inflation?
A brief period of extremely rapid exponential expansion in the very early universe.
Related topics in Particle Physics & Cosmology
Big Bang theory · Cosmic microwave background · Big Bang nucleosynthesis · Dark matter · Dark energy · Critical density