$\kappa-$Minkowski spacetime and a uniformly accelerating observer

Abstract

We analyze the response of a detector with a uniform acceleration $\alpha$ in $\kappa-$Minkowski spacetime using the first order perturbation theory. The monopole detector is coupled to a massless complex scalar field in such a way that it is sensitive to the Lorentz violation due to the noncommutativity of spacetime present in the $\kappa-$deformation. The response function deviates from the thermal distribution of Unruh temperature at the order of $1/\kappa$ and vanishes exponentially as the proper time of the detector exceeds a certain critical time, a logarithmic function of $\kappa$. This suggests that the Unruh temperature becomes not only fuzzy but also eventually decreases to zero in this model.