Skip to content
AsteriaStar
Cosmological parameter · ns

Scalar Spectral Index (ns)

The 'tilt' of the spectrum of primordial density fluctuations laid down by inflation — whether fluctuations have slightly more or less power on large scales than on small. A value just below one is a key prediction of, and constraint on, inflationary models, and is measured from the CMB.

Knowledge connections

Sources

The primary and reference sources this topic draws on.

  • Planck CollaborationESA Planck mission / Planck Collaboration

    Cosmic microwave background maps and the cosmological parameters of the ΛCDM model.