Semiclassical relativistic stars
Abstract We present strong evidence that semiclassical gravity can give place to self-consistent ultracompact stars beyond the Buchdahl limit. We integrate the semiclassical equations of (spherically symmetric) stellar equilibrium for a constant-density classical fluid. The semiclassical contributio...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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Nature Portfolio
2022-09-01
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| Series: | Scientific Reports |
| Online Access: | https://doi.org/10.1038/s41598-022-19836-8 |
| _version_ | 1798001571364077568 |
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| author | Julio Arrechea Carlos Barceló Raúl Carballo-Rubio Luis J. Garay |
| author_facet | Julio Arrechea Carlos Barceló Raúl Carballo-Rubio Luis J. Garay |
| author_sort | Julio Arrechea |
| collection | DOAJ |
| description | Abstract We present strong evidence that semiclassical gravity can give place to self-consistent ultracompact stars beyond the Buchdahl limit. We integrate the semiclassical equations of (spherically symmetric) stellar equilibrium for a constant-density classical fluid. The semiclassical contribution is modelled by a quantum massless scalar field in the only static vacuum state compatible with asymptotic flatness (Boulware vacuum). The Renormalized Stress-Energy Tensor (RSET) is firstly approximated by the analytic Polyakov approximation. This already reveals a crucial difference with respect to purely classical solutions: stars with compactness close to that of a black hole exhibit bounded pressures and curvatures up to a very small central core compared with the star radius. This suggests that a more refined approximation to the RSET at the core may give rise to strictly regular configurations. Following this suggestion, we prove that a minimal deformation of the Polyakov approximation inside the central core is sufficient to produce regular ultracompact stellar configurations. |
| first_indexed | 2024-04-11T11:38:22Z |
| format | Article |
| id | doaj.art-d37e30deab18420ea9e8aceaeb5057ed |
| institution | Directory Open Access Journal |
| issn | 2045-2322 |
| language | English |
| last_indexed | 2024-04-11T11:38:22Z |
| publishDate | 2022-09-01 |
| publisher | Nature Portfolio |
| record_format | Article |
| series | Scientific Reports |
| spelling | doaj.art-d37e30deab18420ea9e8aceaeb5057ed2022-12-22T04:25:54ZengNature PortfolioScientific Reports2045-23222022-09-011211910.1038/s41598-022-19836-8Semiclassical relativistic starsJulio Arrechea0Carlos Barceló1Raúl Carballo-Rubio2Luis J. Garay3Instituto de Astrofísica de Andalucía (IAA-CSIC)Instituto de Astrofísica de Andalucía (IAA-CSIC)CP3-Origins, University of Southern DenmarkDepartamento de Física Teórica and IPARCOS, Universidad Complutense de MadridAbstract We present strong evidence that semiclassical gravity can give place to self-consistent ultracompact stars beyond the Buchdahl limit. We integrate the semiclassical equations of (spherically symmetric) stellar equilibrium for a constant-density classical fluid. The semiclassical contribution is modelled by a quantum massless scalar field in the only static vacuum state compatible with asymptotic flatness (Boulware vacuum). The Renormalized Stress-Energy Tensor (RSET) is firstly approximated by the analytic Polyakov approximation. This already reveals a crucial difference with respect to purely classical solutions: stars with compactness close to that of a black hole exhibit bounded pressures and curvatures up to a very small central core compared with the star radius. This suggests that a more refined approximation to the RSET at the core may give rise to strictly regular configurations. Following this suggestion, we prove that a minimal deformation of the Polyakov approximation inside the central core is sufficient to produce regular ultracompact stellar configurations.https://doi.org/10.1038/s41598-022-19836-8 |
| spellingShingle | Julio Arrechea Carlos Barceló Raúl Carballo-Rubio Luis J. Garay Semiclassical relativistic stars Scientific Reports |
| title | Semiclassical relativistic stars |
| title_full | Semiclassical relativistic stars |
| title_fullStr | Semiclassical relativistic stars |
| title_full_unstemmed | Semiclassical relativistic stars |
| title_short | Semiclassical relativistic stars |
| title_sort | semiclassical relativistic stars |
| url | https://doi.org/10.1038/s41598-022-19836-8 |
| work_keys_str_mv | AT julioarrechea semiclassicalrelativisticstars AT carlosbarcelo semiclassicalrelativisticstars AT raulcarballorubio semiclassicalrelativisticstars AT luisjgaray semiclassicalrelativisticstars |