Maximum-separation inertia bounds
= Maximum-separation inertia bounds
{title2=$B_1R^2\leq I\leq A_1R^2$}
Let $R$ be the actual largest pairwise separation of positive <masses> in their <centre of mass> frame. The <pairwise moment-of-inertia identity> gives $m_{(1)}m_{(2)}R^2/(2M)\leq I\leq R^2\sum_{j<k}m_jm_k/(2M)$. Consequently the scalar inertia is comparable to $R^2$, independently of configuration.