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  • Open Access

Tunable Unruh effect: Accelerated detectors in kappa-Rindler vacua

Arash Azizi*

  • The Institute for Quantum Science and Engineering, Texas A&M University, College Station, Texas 77843, USA

  • *Contact author: sazizi@tamu.edu
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Phys. Rev. D 112, 065018 – Published 22 September, 2025

DOI: https://doi.org/10.1103/52lg-5sxr

Abstract

We study the response of an accelerated Unruh-DeWitt detector to a one-parameter family of “kappa Rindler” vacua, which generalize the standard Unruh effect. These states, parametrized by κ, continuously interpolate between the Rindler (κ→0) and Minkowski (κ=1) vacua. We find the detector registers a perfect thermal bath at a tunable temperature Tκ=κTU. This result establishes a framework for environments perceived as both “hotter” (κ>1) and “colder” (κ<1) than the standard Unruh temperature. We establish this thermality by demonstrating the Kubo-Martin-Schwinger condition for the Wightman function and by analyzing the associated particle creation process. Furthermore, we visualize the spacetime structure of the created field quanta, revealing an intuitive link between the κ-controlled symmetry of the modes and the perceived temperature. Our work provides a comprehensive framework for a modulated Unruh effect, bridging formal quantum field theory with clear visual intuition.

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Phys. Rev. D 112, 065018– Published 22 September, 2025
  • Received 28 August 2025
  • Accepted 5 September 2025
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