{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,31]],"date-time":"2025-10-31T17:06:00Z","timestamp":1761930360804,"version":"build-2065373602"},"reference-count":60,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2024,1,14]],"date-time":"2024-01-14T00:00:00Z","timestamp":1705190400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>The topic of gravitational lensing in the Mannheim\u2013Kazanas solution of Weyl conformal gravity and the Schwarzschild\u2013de Sitter solution in general relativity has featured in numerous publications. These two solutions represent a spherical massive object (lens) embedded in a cosmological background. In both cases, the interest lies in the possible effect of the background non-asymptotically flat spacetime on the geometry of the local light curves, particularly the observed deflection angle of light near the massive object. The main discussion involves possible contributions to the bending angle formula from the cosmological constant \u039b in the Schwarzschild\u2013de Sitter solution and the linear term \u03b3r in the Mannheim\u2013Kazanas metric. These effects from the background geometry, and whether they are significant enough to be important for gravitational lensing, seem to depend on the methodology used to calculate the bending angle. In this paper, we review these techniques and comment on some of the obtained results, particularly those cases that contain unphysical terms in the bending angle formula.<\/jats:p>","DOI":"10.3390\/sym16010101","type":"journal-article","created":{"date-parts":[[2024,1,15]],"date-time":"2024-01-15T04:03:26Z","timestamp":1705291406000},"page":"101","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Gravitational Light Bending in Weyl Gravity and Schwarzschild\u2013de Sitter Spacetime"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3336-0072","authenticated-orcid":false,"given":"Joseph","family":"Sultana","sequence":"first","affiliation":[{"name":"Department of Mathematics, University of Malta, MSD 2080 Msida, Malta"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,1,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"239","DOI":"10.1016\/0375-9601(83)90756-9","article-title":"The cosmological constant and classical tests of general relativity","volume":"97","author":"Islam","year":"1983","journal-title":"Phys. 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