Unruh-DeWitt detector in presence of multiple scalar fields : A Toy Model

TL;DR

This paper explores a toy model where an Unruh-DeWitt detector interacts with multiple scalar fields, revealing a critical acceleration phenomenon absent in single-field interactions, with implications for understanding quantum field effects in accelerated systems.

Contribution

It introduces a novel model of an Unruh-DeWitt detector interacting with multiple scalar fields and uncovers a critical acceleration effect not seen in single-field cases.

Findings

Transition rate depends on acceleration and number of fields

Existence of a critical acceleration for large number of fields

Transition rate becomes significantly high beyond the critical acceleration

Abstract

Applications of Unruh-Fulling (UF) effect are well studied in literature via the interaction of Unruh-DeWitt (UD) detector and {\it single} scalar field. In this work, we investigate a toy model, where the detector is interacting {\it simultaneously} with the {\it multiple} scalar fields. Our study reveals that the transition rate of the system significantly depends on the acceleration of the detector and the number of scalar fields ($n$). For $n\gg1$, there exists a {\it critical acceleration}, beyond which the transition rate becomes drastically high than the accelerations below the critical point. The appearance of such critical point never occurs in case of the interaction of UD detector and {\it single} scalar field.