= Ising Virasoro modules from a Majorana fermion
{c}
{title2=$h=0,\;1/2,\;1/16$}
A chiral <Majorana fermion> with modes $\{b_r,b_s\}=\delta_{r+s,0}$ and $b_r^\dagger=b_{-r}$ has $T=-:\psi\partial\psi:/2$ and <central charge> $1/2$. The even and odd fermion-number parts of its <Neveu–Schwarz sector> give unitary modules with lowest weights $0$ and $1/2$. In its <Ramond sector>, a choice of ground-state zero-mode eigenvalue gives the module of weight $1/16$; the other choice gives an isomorphic <Virasoro algebra> module. Their cyclic highest-weight submodules are irreducible: a positive-energy invariant proper submodule would have a lowest vector orthogonal to every descendant of the original highest vector, which is impossible in a positive inner-product cyclic module.
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