= Asymptotic cold-dark-matter power spectrum
{title2=$P_m\propto k^{n_s}T(k)^2$}
The dimensional <matter power spectrum> contains a factor $k^{n_s}$, rather than $k^{n_s+3}$. The <cosmological transfer function> tends to one below the <matter-radiation equality scale> and to $\ln(k/k_{\rm eq})/(k/k_{\rm eq})^2$ above it. The smooth spectrum therefore scales as $k^{n_s}$ at small wavenumber and $k^{n_s-4}\ln^2(k/k_{\rm eq})$ at large wavenumber. The logarithmic factor records slow cold-matter growth during <radiation domination>. Multiplying by $k^3$ instead produces dimensionless matter power.
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