{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,27]],"date-time":"2026-03-27T22:54:28Z","timestamp":1774652068586,"version":"3.50.1"},"reference-count":15,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2025,6,4]],"date-time":"2025-06-04T00:00:00Z","timestamp":1748995200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Government of Canada"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Axioms"],"abstract":"<jats:p>An approach is presented to resolve key paradoxes in black hole physics through the application of complex Riemannian spacetime. We extend the Schwarzschild metric into the complex domain, employing contour integration techniques to remove singularities while preserving the essential features of the original solution. A new regularized radial coordinate is introduced, leading to a singularity-free description of black hole interiors. Crucially, we demonstrate how this complex extension resolves the long-standing paradox of event horizon formation occurring only in the infinite future of distant observers. By analyzing trajectories in complex spacetime, we show that the horizon can form in finite complex time, reconciling the apparent contradiction between proper and coordinate time descriptions. This approach also provides a framework for the analytic continuation of information across event horizons, resolving the Hawking information paradox. We explore the physical interpretation of the complex extension versus its projection onto real spacetime. The gravitational collapse of a dust sphere with negligible dust is explored in the complex spacetime extension. The approach offers a mathematically rigorous framework for exploring quantum gravity effects within the context of classical general relativity.<\/jats:p>","DOI":"10.3390\/axioms14060440","type":"journal-article","created":{"date-parts":[[2025,6,4]],"date-time":"2025-06-04T06:00:49Z","timestamp":1749016849000},"page":"440","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Complex Riemannian Spacetime: Removal of Black Hole Singularities and Black Hole Paradoxes"],"prefix":"10.3390","volume":"14","author":[{"given":"John W.","family":"Moffat","sequence":"first","affiliation":[{"name":"Perimeter Institute for Theoretical Physics, Waterloo, ON N2L 2Y5, Canada"},{"name":"Department of Physics and Astronomy, University of Waterloo, Waterloo, ON N2L 3G1, Canada"}]}],"member":"1968","published-online":{"date-parts":[[2025,6,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"455","DOI":"10.1103\/PhysRev.56.455","article-title":"On continued gravitational contraction","volume":"56","author":"Oppenheimer","year":"1939","journal-title":"Phys. Rev."},{"key":"ref_2","unstructured":"Moffat, J.W. (2025). Complex Riemannian spacetime and singularity-free black holes and cosmology. arXiv."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Guendelman, E. (2024). Holomorphic gravity and its regularization of locally signed coordinate invariance. arXiv.","DOI":"10.1142\/S0218271824410013"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"175","DOI":"10.1140\/epjc\/s10052-015-3405-x","article-title":"Black holes in modified gravity (MOG)","volume":"75","author":"Moffat","year":"2015","journal-title":"Eur. Phys. J. C"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1743","DOI":"10.1103\/PhysRev.119.1743","article-title":"Maximal extension of Schwarzschild metric","volume":"119","author":"Kruskal","year":"1960","journal-title":"Phys. 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