= Gaussian order-parameter scaling index
{c}
{title2=$\beta_G=(D-2)/4$}
The <Gaussian momentum-shell scaling> has thermal eigenvalue $2$ and source eigenvalue $(D+2)/2$. The formal homogeneous magnetization index is therefore $[D-(D+2)/2]/2=(D-2)/4$. A free quadratic Hamiltonian alone does not possess a stable negative-mass ordered phase, so this index is not a claim of spontaneous magnetization in an unstabilized Gaussian integral. In $2<D<4$, a quartic interaction is relevant at the <Gaussian fixed point> and changes the generic scalar critical behavior.
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