{"id":958,"date":"2017-05-31T21:02:29","date_gmt":"2017-05-31T21:02:29","guid":{"rendered":"http:\/\/physics-complex-systems.fr\/?p=958"},"modified":"2021-06-30T09:49:16","modified_gmt":"2021-06-30T09:49:16","slug":"statistical-field-theory","status":"publish","type":"post","link":"https:\/\/physics-complex-systems.fr\/en\/statistical-field-theory.html","title":{"rendered":"Statistical field theory"},"content":{"rendered":"<p>[vc_row][vc_column css=&#8221;.vc_custom_1496399944725{margin-top: -40px !important;margin-bottom: -20px !important;}&#8221;][vc_separator][\/vc_column][\/vc_row][vc_row][vc_column width=&#8221;1\/2&#8243;][vc_column_text]<\/p>\n<div style=\"text-align: justify; text-justify: inter-word; color: #363131;\">While statistical mechanics deals with averages and fluctuations of global quantities, statistical field theory copes with their spatial fluctuations and correlations. By the so-called coarse-graining procedure, one can define for any quantity of interest a field, and, based on symmetry arguments, an effective Hamiltonian that describes its fluctuations. Advanced tools, such as functional integrals, Feynman diagrams, Wick theorem, and renormalization group (RG), are used to perform calculations. Statistical field theory is particularly adapted to study critical phase transitions, in which scale-free fluctuations are responsible for universal behaviours. The course introduces percolation as a geometrical example of critical phenomena, and develops detailed statistical field theoretical calculations for magnetic systems described by the <i>O(n)<\/i> and <i>\u03c6<sup>4<\/sup><\/i> coarse-grained models, which are found in many other areas of condensed and soft matter physics.<\/div>\n<div><\/div>\n<div><strong>Bibliography<\/strong><\/div>\n<div style=\"color: #363131;\">\n<ul>\n<li><em>Lecture on Phase Transitions and the Renormalization Group<\/em>, N. Goldenfeld, Frontiers in Physics.<\/li>\n<li><em>Statistical Physics of Fields<\/em>, M. Kardar, Cambridge University Press.<\/li>\n<li><em>Principles of Condensed Matter Physics<\/em>, P. Chaikin and T. C. Lubensky, Cambridge University Press.<\/li>\n<\/ul>\n<\/div>\n<p>[\/vc_column_text][vc_column_text]<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-930\" src=\"https:\/\/physics-complex-systems.fr\/wp-content\/uploads\/2017\/05\/mouhanna.jpg\" alt=\"\" width=\"139\" height=\"159\" \/><\/p>\n<p>Dominique Mouhanna<br \/>\n(Sorbonne Universit\u00e9)[\/vc_column_text][\/vc_column][vc_column width=&#8221;1\/2&#8243;][vc_single_image image=&#8221;968&#8243; img_size=&#8221;full&#8221; alignment=&#8221;center&#8221;][\/vc_column][\/vc_row][vc_row][vc_column][vc_column_text]<\/p>\n<div class=\"displaytags\" style=\"color: #363131;\">Keywords : <span class=\"etiquette-key\">coarse-graining<\/span> <span class=\"etiquette-key\">Critical exponents<\/span> <span class=\"etiquette-key\">effective Hamiltonians<\/span> <span class=\"etiquette-key\">Feynman diagrams<\/span> <span class=\"etiquette-key\">functional integrals<\/span> <span class=\"etiquette-key\">percolation<\/span> <span class=\"etiquette-key\">renormalization group<\/span> <span class=\"etiquette-key\">scaling laws<\/span><\/div>\n<p>[\/vc_column_text][\/vc_column][\/vc_row]<\/p>\n","protected":false},"excerpt":{"rendered":"<p>[vc_row][vc_column css=&#8221;.vc_custom_1496399944725{margin-top: -40px !important;margin-bottom: -20px !important;}&#8221;][vc_separator][\/vc_column][\/vc_row][vc_row][vc_column width=&#8221;1\/2&#8243;][vc_column_text] While statistical mechanics deals with averages and fluctuations of global quantities, statistical field theory copes with their spatial&#8230;<\/p>\n","protected":false},"author":5,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[35,11,10],"tags":[30,27,31,33,32,29,34,28],"translation":{"provider":"WPGlobus","version":"2.12.2","language":"en","enabled_languages":["fr","en"],"languages":{"fr":{"title":true,"content":true,"excerpt":false},"en":{"title":false,"content":false,"excerpt":false}}},"_links":{"self":[{"href":"https:\/\/physics-complex-systems.fr\/en\/wp-json\/wp\/v2\/posts\/958"}],"collection":[{"href":"https:\/\/physics-complex-systems.fr\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/physics-complex-systems.fr\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/physics-complex-systems.fr\/en\/wp-json\/wp\/v2\/users\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/physics-complex-systems.fr\/en\/wp-json\/wp\/v2\/comments?post=958"}],"version-history":[{"count":27,"href":"https:\/\/physics-complex-systems.fr\/en\/wp-json\/wp\/v2\/posts\/958\/revisions"}],"predecessor-version":[{"id":5103,"href":"https:\/\/physics-complex-systems.fr\/en\/wp-json\/wp\/v2\/posts\/958\/revisions\/5103"}],"wp:attachment":[{"href":"https:\/\/physics-complex-systems.fr\/en\/wp-json\/wp\/v2\/media?parent=958"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/physics-complex-systems.fr\/en\/wp-json\/wp\/v2\/categories?post=958"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/physics-complex-systems.fr\/en\/wp-json\/wp\/v2\/tags?post=958"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}