= Gyromagnetic-ratio assumption in higher-spin magnetic spectra
The magnetic spectra of a <scalar field> and the <Dirac equation> do not fix every higher-<spin> spectrum. In SI units, a charged mode with a specified <gyromagnetic ratio> corresponding to $g=2$ has the model branches
$$
E^2=m^2c^4+p_z^2c^2+|q|\hbar|B|c^2(2n+1-2m_s).
$$
Here $n=0,1,\ldots$ is the <Landau level> index and $m_s$ is the dimensionless <spin projection> measured along $q\mathbf B$. The power $c^2$ in the magnetic term follows because $|q|\hbar B$ has dimensions of squared <momentum> in SI units; the Gaussian-unit field convention uses a different power of $c$.
For <spin> one, the aligned $n=0,m_s=1,p_z=0$ branch becomes $E^2=m^2c^4-|q|\hbar|B|c^2$. A negative value signals an instability of the assumed background in this model. This extrapolation requires the stated magnetic coupling: <spin> alone does not determine $g$ for an arbitrary higher-spin field.
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