Avenues of Quantum Field Theory In Curved Spacetime 2025

The stress-energy tensor of an Unruh-DeWitt detector

Jan 24, 2025, 2:20 PM

25m

Amphi E040, building E1, ground floor (Tours, France)

Regular Talk

Speaker

João Paulo Pitelli Manoel (State University of Campinas (UNICAMP))

Description

In this talk, we present a theoretical model to describe a finite-size particle detector, focusing on the derivation of its energy-momentum tensor from a covariant Lagrangian formulation. The model encompasses both the quantum field associated with the detector (${\varphi }_{\text{D}}$) and the elements responsible for its localization: a complex scalar field (${\psi }_{\text{C}}$) and a perfect fluid. The local interaction between the detector and the complex field is designed to ensure the quadratic integrability of the detector modes, while the fluid plays a crucial role in defining the spatial profile of ${\psi }_{\text{C}}$, guaranteeing precise localization in space. Furthermore, we explore the physical properties of the resulting energy-momentum tensor, including all system components. We demonstrate that, under general conditions, the derived energy-momentum tensor is physically consistent and satisfies the energy conditions. This approach opens new perspectives for modeling detectors in quantum and relativistic scenarios, offering a robust framework for future applications in field theory.

Presentation materials

Apresentação Tours2.pdf