PHOTONS ARE A DRAG
There's no escape from friction. Objects moving through a vacuum or
even interstellar space feel a universal drag from the photons that
are everywhere, according to the 28 November PRL. Although the drag
is tiny, the researchers believe it may alter cosmologists'
estimates of the time it took for atoms to coalesce after the big
bang. But some cosmologists say the effect, although real, is not
relevant to cosmology.
(V. Mkrtchian et al., Phys. Rev. Lett. 91, 220801)
Link to the paper: http://link.aps.org/abstract/PRL/v91/e220801
COMPLETE Focus story at http://focus.aps.org/story/v12/st22