 Scalar spectral index

ID: scalar-spectral-index

Codex  0 Created 2026-09-24 Updated 2026-09-24

The scalar spectral index describes the departure of the primordial scalar spectrum from scale invariance. To first order in potential slow-roll parameters,

n_{s} - 1 ≃ - 6 ϵ_{V} + 2 η_{V} .

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