  We investigate the response of an Unruh-DeWitt detector coupled to a polymer
quantized massless scalar field in flat spacetime, using the propagator
obtained by Hossain, Husain and Seahra. As this propagator violates Lorentz
invariance, frames moving at different constant velocities are no longer
equivalent. This means that it is possible in principle for even an observer
moving at constant velocity to detect radiation. We show that such an observer
indeed detects radiation. Remarkably, we show that the rate of this radiation
does not decrease with the decrease in the characteristic length scale of
polymer quantization. Thus the radiation cannot be suppressed by making the
polymer length scale arbitrarily small. Our results should bring this theory
within the ambit of low-energy experiments and place a lower limit on the
characteristic polymer length scale.
