  In a recent paper, W. She, J. Yu and R. Feng reported the slight deformations
observed upon transmission of a light pulse through a fairly short length of a
silica glass nano-fiber. Relating the shape and magnitude of these deformations
to the momentum of the light pulse both inside and outside the fiber, these
authors concluded that, within the fiber, the photons carry the Abraham
momentum. In my view, the authors' claim that they have resolved the
Abraham-Minkowski controversy surrounding the momentum of photons inside
dielectric media is premature. A correct interpretation of the experiments of
She et al requires precise calculations that would properly account not only
for the electromagnetic momentum (both inside and outside the fiber) but also
for the Lorentz force exerted on the fiber by the light pulse in its entire
path through this nano-waveguide.
