Isospin multiplet
= Isospin multiplet
{title2=$|I,M\rangle$}
An <isospin multiplet> is an irreducible finite-dimensional <SU(2) representation> with labels $I,M$, where $I\ge0$, $2I$ is an integer and $M=I,I-1,\ldots,-I$. With Hermitian generators, the lowering coefficient is $\sqrt{(I+M)(I-M+1)}$. The <quadratic Casimir operator> has value $I(I+1)$, fixing all ladder norms and the termination at $M=-I$.