{"id":8148,"date":"2024-07-12T14:13:27","date_gmt":"2024-07-12T05:13:27","guid":{"rendered":"https:\/\/unit.nifs.ac.jp\/research\/?post_type=news&#038;p=8148"},"modified":"2024-07-12T14:14:46","modified_gmt":"2024-07-12T05:14:46","slug":"news-8148","status":"publish","type":"news","link":"https:\/\/unit.nifs.ac.jp\/research\/archives\/news\/news-8148","title":{"rendered":"\u8907\u5408\u5927\u57df\u30b7\u30df\u30e5\u30ec\u30fc\u30b7\u30e7\u30f3\u30e6\u30cb\u30c3\u30c8\u30bb\u30df\u30ca\u30fc\uff082024\u5e747\u670823\u65e5\uff09"},"content":{"rendered":"\n<p>[\u65e5\u6642]\u30002024\u5e74 7\u6708 23\u65e5(\u706b) 13:30\u301c15:00<\/p>\n\n\n\n<div style=\"height:24px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<p>[\u5834\u6240]\u3000\u6838\u878d\u5408\u79d1\u5b66\u7814\u7a76\u6240&nbsp;\u7814\u7a76II\u671f\u68df5\u968e509\u30bb\u30df\u30ca\u30fc\u5ba4&nbsp;\uff0b&nbsp;\u30aa\u30f3\u30e9\u30a4\u30f3\u4f75\u7528<\/p>\n\n\n\n<p>\uff08\u63a5\u7d9a\u60c5\u5831\u306f\u5225\u9014\u30e1\u30fc\u30eb\u306b\u3066\u3001\u53c2\u52a0\u7533\u8fbc\u30fb\u62db\u5f85\u3055\u308c\u305f\u65b9\u3078\u304a\u77e5\u3089\u305b\u3057\u307e\u3059\uff09<\/p>\n\n\n\n<div style=\"height:24px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<p>[\u8b1b\u5e2b]\u3000Alain Brizard (Saint Michael\u2019s College)<\/p>\n\n\n\n<div style=\"height:24px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<p>[\u8b1b\u6f14\u984c\u76ee]\u3000Metriplectic structures for reduced Vlasov-Maxwell-Landau equations<\/p>\n\n\n\n<div style=\"height:24px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<p>[\u8b1b\u6f14\u6982\u8981]<br>Structure-preserving algorithms have gained increased attention recently because of the possibility of explicitly satisfying important conservation laws while implementing numerical simulations of complex magnetized plasmas. An important structure found in plasma physics is a\u00a0<em>metriplectic<\/em>\u00a0structure, which combines a dissipationless (Hamiltonian) time evolution, generated by a Hamiltonian functional\u00a0<em>H<\/em>\u00a0and an antisymmetric Hamiltonian bracket [ , ], and a dissipative (collisional) time evolution, generated by an entropy functional\u00a0<em>S<\/em>\u00a0and a symmetric dissipative bracket ( , ). Hence, the time evolution of a generic functional\u00a0F\u00a0is expressed in metriplectic form as\u00a0\u2202<em>F<\/em>\/\u2202t = [<em>F<\/em>,\u00a0<em>H<\/em>] + (<em>F<\/em>,\u00a0<em>S<\/em>). We note here that the entropy functional\u00a0<em>S<\/em>\u00a0is a Casimir functional of the Hamiltonian bracket, i.e., [<em>S<\/em>,\u00a0<em>G<\/em>] = 0 for any functional\u00a0<em>G<\/em>, which immediately leads to an H-theorem:\u00a0\u2202<em>S<\/em>\/\u2202t = (<em>S<\/em>,\u00a0<em>S<\/em>)\u00a0\u2265 0. The metriplectic conservation laws involve functionals\u00a0<em>P<\/em>\u00a0that satisfy [<em>P<\/em>,\u00a0<em>H<\/em>] = 0, which follows from the Noether theorem, and (<em>P<\/em>,\u00a0<em>G<\/em>) = 0 for any functional\u00a0<em>G<\/em>, which serve as constraints on the dissipative bracket.<\/p>\n\n\n\n<div style=\"height:24px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<p>In the first part of this talk, I will review the metriplectic structure of the Vlasov-Maxwell-Landau equations, in which the Hamiltonian bracket was discovered by Morrison (1980,1982) and the dissipative bracket is constructed from the Landau form of the Fokker-Planck collision operator (Kaufman, 1984; Morrison, 1984, 1986). In the second part, I will present new results on the metriplectic structure of the guiding-center Vlasov-Maxwell-Landau equations. The metriplectic structure of the gyrokinetic Vlasov-Maxwell-Landau equations will also be briefly discussed.<\/p>\n\n\n\n<div style=\"height:24px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<p>[\u304a\u554f\u5408\u305b] \u3000cg-sim<img decoding=\"async\" style=\"width: 80px\" src=\"https:\/\/unit.nifs.ac.jp\/research\/wp-content\/themes\/nifs-dev\/img\/img_mail.svg\" alt=\"\"><\/p>\n\n\n\n<div style=\"height:40px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<ul class=\"has-small-font-size wp-block-list\">\n<li>\u8208\u5473\u3092\u304a\u6301\u3061\u306e\u65b9\u306f\u3069\u306a\u305f\u3067\u3082\u3054\u53c2\u52a0\u3044\u305f\u3060\u3051\u307e\u3059\u304c\u3001\u60c5\u5831\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u304a\u3088\u3073\u8cbf\u6613\u7ba1\u7406\u306e\u89b3\u70b9\u304b\u3089\u3001\u4e8b\u524d\u7533\u8fbc\u3092\u304a\u9858\u3044\u3057\u307e\u3059\u3002\u304a\u7533\u8fbc\u307f\u306f\u3001\u6c0f\u540d\u3001\u6240\u5c5e\u3001\u8077\u540d\u307e\u305f\u306f\u5b66\u5e74\u3001\u9023\u7d61\u5148\u30e1\u30fc\u30eb\u30a2\u30c9\u30ec\u30b9\u3092\u660e\u8a18\u306e\u4e0a\u3001cg-sim <code><img decoding=\"async\" style=\"width: 60px\" src=\"https:\/\/unit.nifs.ac.jp\/research\/wp-content\/themes\/nifs-dev\/img\/img_mail.svg\" alt=\"\"><\/code>\u307e\u3067\u30e1\u30fc\u30eb\u306b\u3066\u304a\u9001\u308a\u304f\u3060\u3055\u3044\u3002\u6298\u308a\u8fd4\u3057\u53c2\u52a0\u306e\u53ef\u5426\u3068\u63a5\u7d9a\u60c5\u5831\u3092\u304a\u77e5\u3089\u305b\u3057\u307e\u3059\u3002<\/li>\n\n\n\n<li>\u5f53\u65e5\u3001\u53c2\u52a0\u8005\u540d\u7c3f\u3092\u4f5c\u6210\u3057\u307e\u3059\u3002\u540d\u7c3f\u306f\u6cd5\u306b\u57fa\u3065\u3044\u3066\u958b\u793a\u3055\u308c\u308b\u5834\u5408\u304c\u3042\u308a\u307e\u3059\u3002<\/li>\n\n\n\n<li>\u5404\u6240\u5c5e\u5927\u5b66\u30fb\u6a5f\u95a2\u306b\u304a\u3044\u3066\u7814\u7a76\u502b\u7406\u6559\u80b2\u3092\u53d7\u8b1b\u3057\u305f\u4e0a\u3067\u304a\u7533\u3057\u8fbc\u307f\u304f\u3060\u3055\u3044\u3002<\/li>\n<\/ul>\n","protected":false},"author":9,"featured_media":1986,"menu_order":0,"template":"","meta":{"_acf_changed":false,"footnotes":""},"ppma_author":[347],"class_list":["post-8148","news","type-news","status-publish","has-post-thumbnail","hentry"],"acf":[],"_links":{"self":[{"href":"https:\/\/unit.nifs.ac.jp\/research\/wp-json\/wp\/v2\/news\/8148","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/unit.nifs.ac.jp\/research\/wp-json\/wp\/v2\/news"}],"about":[{"href":"https:\/\/unit.nifs.ac.jp\/research\/wp-json\/wp\/v2\/types\/news"}],"author":[{"embeddable":true,"href":"https:\/\/unit.nifs.ac.jp\/research\/wp-json\/wp\/v2\/users\/9"}],"version-history":[{"count":5,"href":"https:\/\/unit.nifs.ac.jp\/research\/wp-json\/wp\/v2\/news\/8148\/revisions"}],"predecessor-version":[{"id":8154,"href":"https:\/\/unit.nifs.ac.jp\/research\/wp-json\/wp\/v2\/news\/8148\/revisions\/8154"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/unit.nifs.ac.jp\/research\/wp-json\/wp\/v2\/media\/1986"}],"wp:attachment":[{"href":"https:\/\/unit.nifs.ac.jp\/research\/wp-json\/wp\/v2\/media?parent=8148"}],"wp:term":[{"taxonomy":"author","embeddable":true,"href":"https:\/\/unit.nifs.ac.jp\/research\/wp-json\/wp\/v2\/ppma_author?post=8148"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}