Reuse & Permissions

It is not necessary to obtain permission to reuse this article or its components as it is available under the terms of the Creative Commons Attribution 4.0 International license. This license permits unrestricted use, distribution, and reproduction in any medium, provided attribution to the author(s) and the published article's title, journal citation, and DOI are maintained. Please note that some figures may have been included with permission from other third parties. It is your responsibility to obtain the proper permission from the rights holder directly for these figures.

Export citation

Export citation

Choose format for download:

Download Citation
  • Open Access

Vacuum fluctuations and the renormalized stress-energy tensor on a cone with arbitrary boundary conditions

João Paulo M. Pitelli1,*, Ricardo A. Mosna2,†, Victor H. M. Ramos3,‡, and João C. A. Barata3,§

  • *Contact author: pitelli@unicamp.br
  • †Contact author: mosna@unicamp.br
  • ‡Contact author: vhmarques@usp.br
  • §Contact author: jbarata@if.usp.br

Phys. Rev. D 112, 125011 – Published 4 December, 2025

DOI: https://doi.org/10.1103/6fjz-y6y6

Abstract

We analyze the vacuum fluctuations and the stress-energy tensor of a scalar field of mass M 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 M=0 stability is achieved only under Dirichlet boundary conditions, and for M>q 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.

View figure in article

Physics Subject Headings (PhySH)

Article Text

References (24)

  1. A. Staruszkiewicz, Gravitation theory in three-dimensional space, Acta Phys. Pol. 24, 735 (1963).
  2. T. M. Helliwell and D. A. Konkowski, Cosmic strings: Gravitation without local curvature, Am. J. Phys. 55, 401 (1987).
  3. A. Vilenkin, Cosmic strings as gravitational lenses, Astrophys. J. Lett. 282, L51 (1984).
  4. M. V. Sazhin, O. S. Khovanskaya, M. Capaccioli, G. Longo, M. Paolillo, G. Covone, N. A. Grogin, and E. J. Schreier, Gravitational lensing by cosmic strings: What we learn from the CSL-1 case, Mon. Not. R. Astron. Soc. 376, 1731 (2007).
  5. S. Deser and R. Jackiw, Classical and quantum scattering on a cone, Commun. Math. Phys. 118, 495 (1988).
  6. T. M. Helliwell and D. A. Konkowski, Vacuum fluctuations outside cosmic strings, Phys. Rev. D 34, 1918 (1986).
  7. N. Graham, Renormalized quantum stress-energy tensor of a nonzero radius cosmic string, Phys. Rev. D 111, 105028 (2025).
  8. E. R. Bezerra de Mello and A. A. Saharian, Vacuum polarization in a cosmic string spacetime induced by flat boundary, Int. J. Mod. Phys. A 3, 434 (2011).
  9. B. S. Kay and U. M. Studer, Boundary conditions for quantum mechanics on cones and fields around cosmic strings, Commun. Math. Phys. 139, 103 (1991).
  10. A. Ishibashi and R. M. Wald, Dynamics in non-globally-hyperbolic static spacetimes II: General analysis of prescriptions for dynamics, Classical Quantum Gravity 20, 3815 (2003).
  11. M. Reed and B. Simon, Methods of Modern Mathematical Physics, Vol. II: Fourier Analysis, Self-Adjointness (Academic Press, New York, 1975).
  12. B. S. Felipe and J. P. M. Pitelli, Quantum approach to bound states in field theory. Phys. Rev. D 109, 105013 (2024).
  13. W. C. C. Lima, Quantization of unstable linear scalar fields in static spacetimes, Phys. Rev. D 88, 124005 (2013).
  14. A. G. Landulfo, W. C. Lima, G. E. Matsas, and D. A. T. Vanzella, Particle creation due to tachyonic instability in relativistic stars, Phys. Rev. D 86, 104025 (2012).
  15. W. C. C. Lima and D. A. T. Vanzella, Gravity-induced vacuum dominance, Phys. Rev. Lett. 104, 161102 (2010).
  16. W. C. C. Lima, G. E. A. Matsas, and D. A. T. Vanzella, Awaking the vacuum in relativistic stars, Phys. Rev. Lett. 105, 151102 (2010).
  17. V. S. Barroso and J. P. M. Pitelli, Quantum scattering on a cone revisited, Phys. Rev. D 96, 025006 (2017).
  18. B. Allen, B. Kay, and A. C. Ottewill, Long-range effects of cosmic string structure, Phys. Rev. D 53, 6829 (1996).
  19. T. R. Perche, J. P. M. Pitelli, and D. A. T. Vanzella, Stress-energy tensor of an Unruh-DeWitt detector, Phys. Rev. D 111, 045004 (2025).
  20. E. Tjoa and E. Martín-Martínez, Vacuum entanglement harvesting with a zero mode Phys. Rev. D 101, 125020 (2020).
  21. I. Gradshteyn and I. Ryzhik, Table of Integrals, Series and Products (Corrected and Enlarged Edition), edited by by D. Zwillinger (Academic Press, New York, 2014).
  22. H. F. Mota, E. R. Bezerra de Mello, C. H. G. Bessa, and V. B. Bezerra, Light-cone fluctuations in the cosmic string spacetime, Phys. Rev. D 94, 024039 (2016).
  23. Y. Décanini and A. Folacci, Hadamard renormalization of the stress-energy tensor for a quantized scalar field in a general spacetime of arbitrary dimension, Phys. Rev. D 78, 044025 (2008).
  24. H. R. C. Ferreira and J. Louko, Renormalized vacuum polarization on rotating warped black holes, Phys. Rev. D 91, 024038 (2015).

Outline

Information

Sign In to Your Journals Account

Filter

Filter

Article Lookup

Enter a citation