  According to the scientific literature, the momentum of a photon in a simple
linear dielectric is either $\hbar\omega/(nc)$ or $n\hbar\omega/c$ with a unit
vector ${\bf \hat e}_k$ in the direction of propagation. These momentums are
typically used to argue the century-old Abraham--Minkowski controversy in which
the momentum density of the electromagnetic field in a dielectric is either the
Abraham momentum density, ${\bf g}_A={\bf E}\times{\bf H}/c$, or the Minkowski
momentum density, ${\bf g}_M={\bf D}\times{\bf B}/c$. The elementary optical
excitations, photons, are typically known as polaritions in the particular case
of light traveling in a dielectric medium. Applying the relativistic energy
formula, we find that the total momentum that is attributable to a polariton in
a dielectric is $\hbar\omega{\bf \hat e}_k/c$ corresponding to a total momentum
density ${\bf g}_T=n{\bf E}\times{\bf B}/c$.
