  The Unruh effect is the prediction that an accelerating object perceives its
surroundings as a bath of thermal radiation even if it accelerates in vacuum.
The Unruh effect is believed to be very difficult to observe in the experiment,
since an observer accelerating at g=9.8 m/s2 should see vacuum temperature of
only 4x10^-20 K. Here we demonstrate that photons in metamaterial waveguides
may behave as massive quasi-particles accelerating at up to 10^24 g, which is
about twelve orders of magnitude larger than the surface acceleration near a
stellar black hole. These record high accelerations may enable experimental
studies of the Unruh effect and the loss of quantum entanglement in strongly
accelerated reference frames.
