2006/11/30 by Shih-Yuin Lin, B. L. Hu · 6 citations
Engineering · Physics and Astronomy · #Advanced Thermodynamics and Statistical Mechanics #Detector #Minkowski space #Optics #Physics #Quantum #Quantum Electrodynamics and Casimir Effect #Quantum electrodynamics #Quantum entanglement #Quantum mechanics #Statistical physics #Thermal Radiation and Cooling Technologies #Unruh effect #gr-qc #quant-ph
paper · pdf · doi:10.1103/physrevd.76.064008
published as Phys.Rev.D76:064008,2007 · 12 pages, 2 figures, no alteration of the main findings and claims but includes at the prompting of the referees discussions
openalex publication_date 2007/09/12 · arxiv created 2007/09/13 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Using nonperturbative results obtained recently for a uniformly accelerated Unruh-DeWitt detector, we discover new features in the dynamical evolution of the detector's internal degree of freedom, and identified the Unruh effect derived originally from time-dependent perturbation theory as operative in the ultraweak coupling and ultrahigh acceleration limits. The mutual interaction between the detector and the field engenders entanglement between them, and tracing out the field leads to a mixed state of the detector even for a detector at rest in Minkowski vacuum. Our findings based on this exact solution show clearly the differences from the ordinary result where the quantum field's backreaction is ignored in that the detector no longer behaves like a perfect thermometer. From a calculation of the evolution of the reduced density matrix of the detector, we find that the transition probability from the initial ground state over an infinitely long duration of interaction derived from time-dependent perturbation theory is existent in the exact solution only in transient under special limiting conditions corresponding to the Markovian regime. Furthermore, the detector at late times never sees an exact Boltzmann distribution over the energy eigenstates of the free detector, thus in the non-Markovian regime covering a wider range of parameters the Unruh temperature cannot be identified inside the detector.