{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,11]],"date-time":"2026-04-11T13:20:57Z","timestamp":1775913657580,"version":"3.50.1"},"reference-count":81,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2025,9,20]],"date-time":"2025-09-20T00:00:00Z","timestamp":1758326400000},"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 classification of exact solutions of Maxwell vacuum equations for pseudo-Riemannian spaces with spatial symmetry (homogeneous non-null spaces in Petrov) in the presence of electromagnetic fields invariant with respect to the action of the group of space motions is summarized. A new classification method is used, common to all homogeneous zero spaces of Petrov. The method is based on the use of canonical reper vectors and on the use of a new approach to the systematization of solutions. The classification results are presented in a form more convenient for further use. Using the previously made refinement of the classification of Petrov spaces, the classification of exact solutions of Maxwell vacuum equations for spaces with the group of motions G3(VIII) is completed.<\/jats:p>","DOI":"10.3390\/sym17091574","type":"journal-article","created":{"date-parts":[[2025,9,22]],"date-time":"2025-09-22T08:37:39Z","timestamp":1758530259000},"page":"1574","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Exact Solutions of Maxwell Vacuum Equations in Petrov Homogeneous Non-Null Spaces"],"prefix":"10.3390","volume":"17","author":[{"given":"Valery V.","family":"Obukhov","sequence":"first","affiliation":[{"name":"Department of Research and Development, Tomsk State Pedagogical University, 60 Kievskaya St., Tomsk 634041, Russia"},{"name":"Laboratory for Theoretical Cosmology, International Center of Gravity and Cosmos, Tomsk State University of Control Systems and Radio Electronics, 36, Lenin Avenue, Tomsk 634050, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,9,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"145","DOI":"10.1007\/BF01445366","article-title":"Uber die intagration der Hamiltonschen differentialechung mittels separation der variablen","volume":"49","year":"1897","journal-title":"Math. 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