= One-loop two-point divergence in six-dimensional cubic scalar theory
{title2=$I_{\mathrm{div}}(k)=-g^2(m^2+k^2/6)/[(4\pi)^3\epsilon]$}
The two-vertex cubic bubble in $d=6-\epsilon$ dimensions has the displayed amputated pole. A <Feynman parameter> gives mass $m^2+x(1-x)k^2$, and $\Gamma(-1+\epsilon/2)$ supplies the pole. The full propagator receives $D_0^2 I$, while its inverse receives $-I$. This sign distinguishes a two-point insertion from an inverse-propagator correction.
Back to article page
