On the analytic generalization of particle deflection in the weak field regime and shadow size in light of EHT constraints for Schwarzschild-like black hole solutions

Abstract In this paper, an analytic generalization of the weak field deflection angle (WDA) is derived by utilizing the current non-asymptotically flat generalization of the Gauss–Bonnet theorem. The derived formula is valid for any Schwarzschild-like spacetime, which deviates from the classical Sch...

Full description

Saved in:
Bibliographic Details
Main Author: Reggie C. Pantig
Format: Article
Language:English
Published: SpringerOpen 2025-01-01
Series:European Physical Journal C: Particles and Fields
Online Access:https://doi.org/10.1140/epjc/s10052-025-13766-1
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1832585458698158080
author Reggie C. Pantig
author_facet Reggie C. Pantig
author_sort Reggie C. Pantig
collection DOAJ
description Abstract In this paper, an analytic generalization of the weak field deflection angle (WDA) is derived by utilizing the current non-asymptotically flat generalization of the Gauss–Bonnet theorem. The derived formula is valid for any Schwarzschild-like spacetime, which deviates from the classical Schwarzschild case through some constant parameters. This work provided four examples, including Schwarzschild-like solutions in the context of Bumblebee gravity theory and the Kalb–Ramond framework, as well as one example from a black hole surrounded by soliton dark matter. These examples explore distinct mechanisms of Lorentz symmetry breaking, with results that are either new or in agreement with existing literature. The WDA formula provided a simple calculation, where approximations based on some conditions can be done directly on it, skipping the preliminary steps. For the shadow size analysis, it is shown how it depends solely on the parameter associated with the metric coefficient in the time coordinate. A general formula for the constrained parameter is also derived based on the Event Horizon Collaboration (EHT) observational results. Finally, the work realized further possible generalizations on other black hole models, such as RN-like, dS/AdS-like black hole solutions, and even black hole solutions in higher dimensions.
format Article
id doaj-art-de6a2e9721df4bb888af7027fe753b92
institution Kabale University
issn 1434-6052
language English
publishDate 2025-01-01
publisher SpringerOpen
record_format Article
series European Physical Journal C: Particles and Fields
spelling doaj-art-de6a2e9721df4bb888af7027fe753b922025-01-26T12:49:42ZengSpringerOpenEuropean Physical Journal C: Particles and Fields1434-60522025-01-0185111110.1140/epjc/s10052-025-13766-1On the analytic generalization of particle deflection in the weak field regime and shadow size in light of EHT constraints for Schwarzschild-like black hole solutionsReggie C. Pantig0Physics Department, Mapúa UniversityAbstract In this paper, an analytic generalization of the weak field deflection angle (WDA) is derived by utilizing the current non-asymptotically flat generalization of the Gauss–Bonnet theorem. The derived formula is valid for any Schwarzschild-like spacetime, which deviates from the classical Schwarzschild case through some constant parameters. This work provided four examples, including Schwarzschild-like solutions in the context of Bumblebee gravity theory and the Kalb–Ramond framework, as well as one example from a black hole surrounded by soliton dark matter. These examples explore distinct mechanisms of Lorentz symmetry breaking, with results that are either new or in agreement with existing literature. The WDA formula provided a simple calculation, where approximations based on some conditions can be done directly on it, skipping the preliminary steps. For the shadow size analysis, it is shown how it depends solely on the parameter associated with the metric coefficient in the time coordinate. A general formula for the constrained parameter is also derived based on the Event Horizon Collaboration (EHT) observational results. Finally, the work realized further possible generalizations on other black hole models, such as RN-like, dS/AdS-like black hole solutions, and even black hole solutions in higher dimensions.https://doi.org/10.1140/epjc/s10052-025-13766-1
spellingShingle Reggie C. Pantig
On the analytic generalization of particle deflection in the weak field regime and shadow size in light of EHT constraints for Schwarzschild-like black hole solutions
European Physical Journal C: Particles and Fields
title On the analytic generalization of particle deflection in the weak field regime and shadow size in light of EHT constraints for Schwarzschild-like black hole solutions
title_full On the analytic generalization of particle deflection in the weak field regime and shadow size in light of EHT constraints for Schwarzschild-like black hole solutions
title_fullStr On the analytic generalization of particle deflection in the weak field regime and shadow size in light of EHT constraints for Schwarzschild-like black hole solutions
title_full_unstemmed On the analytic generalization of particle deflection in the weak field regime and shadow size in light of EHT constraints for Schwarzschild-like black hole solutions
title_short On the analytic generalization of particle deflection in the weak field regime and shadow size in light of EHT constraints for Schwarzschild-like black hole solutions
title_sort on the analytic generalization of particle deflection in the weak field regime and shadow size in light of eht constraints for schwarzschild like black hole solutions
url https://doi.org/10.1140/epjc/s10052-025-13766-1
work_keys_str_mv AT reggiecpantig ontheanalyticgeneralizationofparticledeflectionintheweakfieldregimeandshadowsizeinlightofehtconstraintsforschwarzschildlikeblackholesolutions