Superluminal dispersion relations and the Unruh effect

Understand

In the context of quantum gravity phenomenology, we study the Unruh effect in the presence of superluminal dispersion relations.

• In particular, we estimate the response function and the probability rate for an accelerated detector coupled to a massless scalar field, whose dispersion relation becomes essentially quadratic beyond a threshold momentum $k_p$.
• By means of perturbative analysis, we show that superluminal dispersion induces a correction to the Planckian spectrum, which tends to vanish as $k_p$ increases.