2025/09/24 by João Paulo M. Pitelli, Ricardo A. Mosna, Pitelli, João Paulo M. +7 · 1 citation
Physics and Astronomy · #Quantum Electrodynamics and Casimir Effect #Noncommutative and Quantum Gravity Theories #Cosmology and Gravitation Theories
paper · pdf · doi:10.1103/6fjz-y6y6
We analyze the vacuum fluctuations and the stress-energy tensor of a scalar field of mass <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"> <a:mi>M</a:mi> </a:math> in a conical spacetime, where the topological singularity at the apex requires boundary conditions for the field equation. The necessity of boundary conditions was established by Kay and Studer in the early 1990s, while for <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"> <c:mi>M</c:mi> <c:mo>=</c:mo> <c:mn>0</c:mn> </c:math> stability is achieved only under Dirichlet boundary conditions, and for <e:math xmlns:e="http://www.w3.org/1998/Math/MathML" display="inline"> <e:mi>M</e:mi> <e:mo>></e:mo> <e:mi>q</e:mi> </e:math> the field is stable and a localized mode emerges. This mode admits a natural interpretation as a covariant model of an extended particle detector, which allows us to investigate how such detectors modify the local vacuum structure. In this framework, the renormalized stress-energy tensor offers a natural way to quantify the influence of the detector on the surrounding spacetime.