Inflation from periodic extra dimensions

Understand

We discuss a realization of a small field inflation based on string inspired supergravities.

• In theories accompanying extra dimensions, compactification of them with small radii is required for realistic situations.
• Since the extra dimension can have a periodicity, there will appear (quasi-)periodic functions under transformations of moduli of the extra dimensions in low energy scales.
• Such a periodic property can lead to a UV completion of so-called multi-natural inflation model where inflaton potential consists of a sum of multiple sinusoidal functions with a decay constant smaller than the Planck scale.