{"id":96,"date":"2016-01-17T22:17:37","date_gmt":"2016-01-17T21:17:37","guid":{"rendered":"http:\/\/perso.ens-lyon.fr\/ghys\/?page_id=96"},"modified":"2025-05-29T17:36:34","modified_gmt":"2025-05-29T16:36:34","slug":"action-2","status":"publish","type":"page","link":"https:\/\/perso.ens-lyon.fr\/ghys\/action-2\/","title":{"rendered":"Action"},"content":{"rendered":"\n<p>A wonderful&nbsp;mathematical party<a href=\"http:\/\/geometrie.math.cnrs.fr\/english.html\" class=\"broken_link\">&nbsp;<\/a>&nbsp;took place in Lyon from June 27th to July 3rd 2015.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><strong><span style=\"color: #339966;\"><a href=\"http:\/\/geometrie.math.cnrs.fr\/english.html\" class=\"broken_link\">Geometries in action.<\/a><\/span><\/strong><\/h2>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter\"><a href=\"https:\/\/perso.ens-lyon.fr\/ghys\/wp-content\/uploads\/2016\/01\/Gateau.jpg\"><img loading=\"lazy\" decoding=\"async\" width=\"300\" height=\"225\" src=\"https:\/\/perso.ens-lyon.fr\/ghys\/wp-content\/uploads\/2016\/01\/Gateau-300x225.jpg\" alt=\"\" class=\"wp-image-110\" srcset=\"https:\/\/perso.ens-lyon.fr\/ghys\/wp-content\/uploads\/2016\/01\/Gateau-300x225.jpg 300w, https:\/\/perso.ens-lyon.fr\/ghys\/wp-content\/uploads\/2016\/01\/Gateau-768x576.jpg 768w, https:\/\/perso.ens-lyon.fr\/ghys\/wp-content\/uploads\/2016\/01\/Gateau.jpg 1024w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><\/figure><\/div>\n\n\n<p class=\"has-drop-cap\">I would like to thank&nbsp;the organizers, all friends and colleagues, who contributed to this happy moment, not only from the mathematical point of view. Thanks to all the speakers: it was a great honor to have them in Lyon.<\/p>\n\n\n\n<p>I like very much the plural in \u00ab\u00a0geometries\u00a0\u00bb. With \u00ab\u00a0In action\u00a0\u00bb as a suffix, it looks even better. The conference was a big&nbsp;success: no doubt that among the many meetings that I attended this one is&nbsp;my favorite \ud83d\ude42<\/p>\n\n\n\n<p>The weekend before the Conference, a more \u00ab\u00a0private\u00a0\u00bb party was organized in&nbsp;<a href=\"http:\/\/www.chateaudegoutelas.fr\/\" class=\"broken_link\">ch\u00e2teau de Goutelas<\/a>, with all my former students, some of their own students, and some of my closest mathematical friends. I have been knowing this magical place&nbsp;<a href=\"http:\/\/perso.ens-lyon.fr\/gaboriau\/Goutelas\/Goutelas.html\">for a long time<\/a>. The weather was gorgeous, the talks were excellent, and the atmosphere unforgettable.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>The\u00a0<a href=\"http:\/\/geometrie.math.cnrs.fr\/english.html\" class=\"broken_link\">Conference site<\/a>.<\/li>\n\n\n\n<li>Some photos of the\u00a0<a href=\"https:\/\/perso.ens-lyon.fr\/ghys\/Goutelas\/index.html\">Goutelas weekend<\/a>.<\/li>\n\n\n\n<li>Some photos of the\u00a0<a href=\"https:\/\/perso.ens-lyon.fr\/ghys\/Colloque\/index.html\" target=\"_blank\" rel=\"noopener noreferrer\">Conference<\/a>.<\/li>\n<\/ul>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter\"><img loading=\"lazy\" decoding=\"async\" width=\"300\" height=\"225\" src=\"https:\/\/perso.ens-lyon.fr\/ghys\/wp-content\/uploads\/2016\/01\/amphi-300x225.jpg\" alt=\"amphi\" class=\"wp-image-603\" srcset=\"https:\/\/perso.ens-lyon.fr\/ghys\/wp-content\/uploads\/2016\/01\/amphi-300x225.jpg 300w, https:\/\/perso.ens-lyon.fr\/ghys\/wp-content\/uploads\/2016\/01\/amphi-1024x768.jpg 1024w, https:\/\/perso.ens-lyon.fr\/ghys\/wp-content\/uploads\/2016\/01\/amphi.jpg 1600w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/figure><\/div>\n\n\n<h2 class=\"wp-block-heading\">Again, Villers le lac, in Jura, 23-26 May 2025, Ten years later !<\/h2>\n\n\n\n<p>Warm, \u00ab\u00a0family\u00a0\u00bb moments. Thank you!<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"683\" src=\"https:\/\/perso.ens-lyon.fr\/ghys\/wp-content\/uploads\/2025\/05\/202505_Anniv-Etienne-Ghys_P1224789_HD-1024x683.jpg\" alt=\"\" class=\"wp-image-2754\" srcset=\"https:\/\/perso.ens-lyon.fr\/ghys\/wp-content\/uploads\/2025\/05\/202505_Anniv-Etienne-Ghys_P1224789_HD-1024x683.jpg 1024w, https:\/\/perso.ens-lyon.fr\/ghys\/wp-content\/uploads\/2025\/05\/202505_Anniv-Etienne-Ghys_P1224789_HD-300x200.jpg 300w, https:\/\/perso.ens-lyon.fr\/ghys\/wp-content\/uploads\/2025\/05\/202505_Anniv-Etienne-Ghys_P1224789_HD-150x100.jpg 150w, https:\/\/perso.ens-lyon.fr\/ghys\/wp-content\/uploads\/2025\/05\/202505_Anniv-Etienne-Ghys_P1224789_HD-1536x1024.jpg 1536w, https:\/\/perso.ens-lyon.fr\/ghys\/wp-content\/uploads\/2025\/05\/202505_Anniv-Etienne-Ghys_P1224789_HD-2048x1365.jpg 2048w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"768\" src=\"https:\/\/perso.ens-lyon.fr\/ghys\/wp-content\/uploads\/2025\/05\/IMG_8293-1024x768.jpeg\" alt=\"\" class=\"wp-image-2756\" srcset=\"https:\/\/perso.ens-lyon.fr\/ghys\/wp-content\/uploads\/2025\/05\/IMG_8293-1024x768.jpeg 1024w, https:\/\/perso.ens-lyon.fr\/ghys\/wp-content\/uploads\/2025\/05\/IMG_8293-300x225.jpeg 300w, https:\/\/perso.ens-lyon.fr\/ghys\/wp-content\/uploads\/2025\/05\/IMG_8293-150x113.jpeg 150w, https:\/\/perso.ens-lyon.fr\/ghys\/wp-content\/uploads\/2025\/05\/IMG_8293-1536x1152.jpeg 1536w, https:\/\/perso.ens-lyon.fr\/ghys\/wp-content\/uploads\/2025\/05\/IMG_8293-2048x1536.jpeg 2048w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"661\" src=\"https:\/\/perso.ens-lyon.fr\/ghys\/wp-content\/uploads\/2025\/05\/IMG_8291-1024x661.jpeg\" alt=\"\" class=\"wp-image-2755\" srcset=\"https:\/\/perso.ens-lyon.fr\/ghys\/wp-content\/uploads\/2025\/05\/IMG_8291-1024x661.jpeg 1024w, https:\/\/perso.ens-lyon.fr\/ghys\/wp-content\/uploads\/2025\/05\/IMG_8291-300x194.jpeg 300w, https:\/\/perso.ens-lyon.fr\/ghys\/wp-content\/uploads\/2025\/05\/IMG_8291-150x97.jpeg 150w, https:\/\/perso.ens-lyon.fr\/ghys\/wp-content\/uploads\/2025\/05\/IMG_8291-1536x992.jpeg 1536w, https:\/\/perso.ens-lyon.fr\/ghys\/wp-content\/uploads\/2025\/05\/IMG_8291-2048x1323.jpeg 2048w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>A wonderful&nbsp;mathematical party&nbsp;&nbsp;took place in Lyon from June 27th to July 3rd 2015. Geometries in action. I would like to thank&nbsp;the organizers, all friends and colleagues, who contributed to this happy moment, not only from the mathematical point of view. Thanks to all the speakers: it was a great honor to have them in Lyon. &hellip; <a href=\"https:\/\/perso.ens-lyon.fr\/ghys\/action-2\/\" class=\"more-link\">Continuer la lecture de <span class=\"screen-reader-text\">Action<\/span> <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_uag_custom_page_level_css":"","ub_ctt_via":"","_exactmetrics_skip_tracking":false,"_exactmetrics_sitenote_active":false,"_exactmetrics_sitenote_note":"","_exactmetrics_sitenote_category":0,"episode_type":"","audio_file":"","cover_image":"","cover_image_id":"","duration":"","filesize":"","date_recorded":"","explicit":"","block":"","itunes_episode_number":"","itunes_title":"","itunes_season_number":"","itunes_episode_type":"","filesize_raw":"","footnotes":""},"class_list":["post-96","page","type-page","status-publish","hentry"],"featured_image_src":null,"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v25.4 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>Action - \u00c9tienne Ghys<\/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:\/\/perso.ens-lyon.fr\/ghys\/action-2\/\" \/>\n<meta property=\"og:locale\" content=\"fr_FR\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Action - \u00c9tienne Ghys\" \/>\n<meta property=\"og:description\" content=\"A wonderful&nbsp;mathematical party&nbsp;&nbsp;took place in Lyon from June 27th to July 3rd 2015. Geometries in action. I would like to thank&nbsp;the organizers, all friends and colleagues, who contributed to this happy moment, not only from the mathematical point of view. Thanks to all the speakers: it was a great honor to have them in Lyon. &hellip; Continuer la lecture de Action &rarr;\" \/>\n<meta property=\"og:url\" content=\"https:\/\/perso.ens-lyon.fr\/ghys\/action-2\/\" \/>\n<meta property=\"og:site_name\" content=\"\u00c9tienne Ghys\" \/>\n<meta property=\"article:modified_time\" content=\"2025-05-29T16:36:34+00:00\" \/>\n<meta property=\"og:image\" content=\"http:\/\/perso.ens-lyon.fr\/ghys\/wp-content\/uploads\/2016\/01\/Gateau-300x225.jpg\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Dur\u00e9e de lecture estim\u00e9e\" \/>\n\t<meta name=\"twitter:data1\" content=\"2 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\/\/perso.ens-lyon.fr\/ghys\/action-2\/\",\"url\":\"https:\/\/perso.ens-lyon.fr\/ghys\/action-2\/\",\"name\":\"Action - \u00c9tienne Ghys\",\"isPartOf\":{\"@id\":\"https:\/\/perso.ens-lyon.fr\/ghys\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\/\/perso.ens-lyon.fr\/ghys\/action-2\/#primaryimage\"},\"image\":{\"@id\":\"https:\/\/perso.ens-lyon.fr\/ghys\/action-2\/#primaryimage\"},\"thumbnailUrl\":\"http:\/\/perso.ens-lyon.fr\/ghys\/wp-content\/uploads\/2016\/01\/Gateau-300x225.jpg\",\"datePublished\":\"2016-01-17T21:17:37+00:00\",\"dateModified\":\"2025-05-29T16:36:34+00:00\",\"breadcrumb\":{\"@id\":\"https:\/\/perso.ens-lyon.fr\/ghys\/action-2\/#breadcrumb\"},\"inLanguage\":\"fr-FR\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\/\/perso.ens-lyon.fr\/ghys\/action-2\/\"]}]},{\"@type\":\"ImageObject\",\"inLanguage\":\"fr-FR\",\"@id\":\"https:\/\/perso.ens-lyon.fr\/ghys\/action-2\/#primaryimage\",\"url\":\"http:\/\/perso.ens-lyon.fr\/ghys\/wp-content\/uploads\/2016\/01\/Gateau-300x225.jpg\",\"contentUrl\":\"http:\/\/perso.ens-lyon.fr\/ghys\/wp-content\/uploads\/2016\/01\/Gateau-300x225.jpg\"},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\/\/perso.ens-lyon.fr\/ghys\/action-2\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Accueil\",\"item\":\"https:\/\/perso.ens-lyon.fr\/ghys\/accueil\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Action\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\/\/perso.ens-lyon.fr\/ghys\/#website\",\"url\":\"https:\/\/perso.ens-lyon.fr\/ghys\/\",\"name\":\"\u00c9tienne Ghys\",\"description\":\"\",\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\/\/perso.ens-lyon.fr\/ghys\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"fr-FR\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"Action - \u00c9tienne Ghys","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/perso.ens-lyon.fr\/ghys\/action-2\/","og_locale":"fr_FR","og_type":"article","og_title":"Action - \u00c9tienne Ghys","og_description":"A wonderful&nbsp;mathematical party&nbsp;&nbsp;took place in Lyon from June 27th to July 3rd 2015. 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Geometries in action. I would like to thank&nbsp;the organizers, all friends and colleagues, who contributed to this happy moment, not only from the mathematical point of view. Thanks to all the speakers: it was a great honor to have them in Lyon.\u2026","_links":{"self":[{"href":"https:\/\/perso.ens-lyon.fr\/ghys\/wp-json\/wp\/v2\/pages\/96","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/perso.ens-lyon.fr\/ghys\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/perso.ens-lyon.fr\/ghys\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/perso.ens-lyon.fr\/ghys\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/perso.ens-lyon.fr\/ghys\/wp-json\/wp\/v2\/comments?post=96"}],"version-history":[{"count":26,"href":"https:\/\/perso.ens-lyon.fr\/ghys\/wp-json\/wp\/v2\/pages\/96\/revisions"}],"predecessor-version":[{"id":2761,"href":"https:\/\/perso.ens-lyon.fr\/ghys\/wp-json\/wp\/v2\/pages\/96\/revisions\/2761"}],"wp:attachment":[{"href":"https:\/\/perso.ens-lyon.fr\/ghys\/wp-json\/wp\/v2\/media?parent=96"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}