{"id":627956,"date":"2026-01-19T00:54:32","date_gmt":"2026-01-18T23:54:32","guid":{"rendered":"https:\/\/cronologia-universale.it\/1999-22\/"},"modified":"2026-01-19T00:54:32","modified_gmt":"2026-01-18T23:54:32","slug":"1991-3","status":"publish","type":"post","link":"https:\/\/cronologia-universale.it\/en\/1991-3\/","title":{"rendered":"1991"},"content":{"rendered":"

Chinese mathematician Quidong Wang, who teaches at the University of Arizona’s Department of Mathematics, extends the partial solution to the Three-Body Problem found in 1912 by Finnish mathematician Karl Frithiof Sundman to any number of bodies. Sundman discovered that the presence of chaos, particularly in the Three-Body Problem, does not preclude solutions based on series, but these are almost always valid, rather than valid. His series converge unless the initial state has zero momentum, but such states are infinitely rare.<\/p>\n","protected":false},"excerpt":{"rendered":"

Chinese mathematician Quidong Wang, who teaches at the University of Arizona’s Department of Mathematics, extends…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[35],"tags":[],"class_list":["post-627956","post","type-post","status-publish","format-standard","hentry","category-ev-en"],"acf":[],"yoast_head":"\n1991 - Cronologia Universale<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/cronologia-universale.it\/en\/1991-3\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"1991 - Cronologia Universale\" \/>\n<meta property=\"og:description\" content=\"Chinese mathematician Quidong Wang, who teaches at the University of Arizona’s Department of Mathematics, extends...\" \/>\n<meta property=\"og:url\" content=\"https:\/\/cronologia-universale.it\/en\/1991-3\/\" \/>\n<meta property=\"og:site_name\" content=\"Cronologia Universale\" \/>\n<meta property=\"article:published_time\" content=\"2026-01-18T23:54:32+00:00\" \/>\n<meta name=\"author\" content=\"Rick\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"Rick\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\/\/cronologia-universale.it\/en\/1991-3\/\",\"url\":\"https:\/\/cronologia-universale.it\/en\/1991-3\/\",\"name\":\"1991 - 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