= Ferromagnetic ground-state multiplet
{title2=$S_{\rm tot}=NS,\quad\dim=2NS+1$}
A connected isotropic spin-$S$ ferromagnet with positive exchanges has a fully polarized <ground state> and a maximal-total-spin multiplet. For $N$ sites the total spin is $NS$, with $2NS+1$ magnetic states generated by total-spin lowering. Global rotations span the same degenerate space. Slowly varying reorientations produce gapless <ferromagnetic magnons>; finite-volume degeneracy must be distinguished from a thermodynamic statement about spontaneous order.
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