{"id":640,"date":"2008-09-25T00:17:36","date_gmt":"2008-09-25T05:17:36","guid":{"rendered":"http:\/\/arxivblog.com\/?p=640"},"modified":"2008-09-25T00:18:45","modified_gmt":"2008-09-25T05:18:45","slug":"new-fractal-pattern-found-in-milk-and-coffee","status":"publish","type":"post","link":"http:\/\/arxivblog.com\/?p=640","title":{"rendered":"New fractal pattern found in milk and coffee"},"content":{"rendered":"<p><a href=\"http:\/\/arxivblog.com\/wp-content\/uploads\/2008\/09\/coffee-fractal.jpg\" title=\"coffee-fractal.jpg\"><img decoding=\"async\" src=\"http:\/\/arxivblog.com\/wp-content\/uploads\/2008\/09\/coffee-fractal.thumbnail.jpg\" alt=\"coffee-fractal.jpg\" \/><\/a><\/p>\n<p>Next time you stare into your 9am double tall latte, look with new respect. Japanese scientists have discovered a new type of fractal in the patterns coffee makes as mixes with milk.<\/p>\n<p>Placing a heavier fluid onto  a lighter fluid always results in an disturbance at their boundary<br \/>\nknown as a Rayleigh\u2013Taylor instability.<\/p>\n<p>Michiko Shimokawa and Shonosuke Ohta from Kyushu University in Japan placed coffee (Nescafe&#8217;s Gold Blend, if you must know) on top of ordinary milk, which is lighter, and watched how gravity and surface tension compete in a way that leads to Rayleigh-Taylor instability.<\/p>\n<p>As soon as the coffee droplet is placed on the surface, the coffee solution spreads out creating a fractal pattern. But this is a different kind of pattern from the ordinary fractals seen in river branches, and bacterial colonies,  which continue to grow and increase in area.<\/p>\n<p>Instead,  in coffee, parts of the pattern disappear as they are sucked into the milk by gravity. The result is a shifting pattern, parts of which continually disappear..<\/p>\n<p>Shimokawa and Ohta say this behaviour closely matches that of a <a href=\"http:\/\/en.wikipedia.org\/wiki\/Sierpinski_carpet\">Sierpinski carpet<\/a> which is formed by cutting a square into 9 smaller squares in a 3-by-3 grid. The central square is then removed and the procedure applied to the remaining 8 squares <em>ad infinitum<\/em>. This creates\u00a0 a fractal structure with dimension 1.88.<\/p>\n<p>That&#8217;s the same dimension that the coffee fractals turn out to have. And there are other similarities too, such as the disappearing patterns.<\/p>\n<p>This, say the Japanese pair, strongly implies that the coffee fractal must form in the same way as a Sierpinski carpet, following similar rules. Intriguing!<\/p>\n<p>So come on chaps: what are these rules and how do they come about in a system dominated by the complexity of Rayleigh-Taylor instabilities?<\/p>\n<p>Ref:  <a href=\"http:\/\/arxiv.org\/abs\/0809.2458\">arxiv.org\/abs\/0809.2458<\/a>: Annihilative fractals of coffee on milk formed by Rayleigh\u2013Taylor instability<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Next time you stare into your 9am double tall latte, look with new respect. Japanese scientists have discovered a new type of fractal in the patterns coffee makes as mixes with milk. Placing a heavier fluid onto a lighter fluid always results in an disturbance at their boundary known as a Rayleigh\u2013Taylor instability. Michiko Shimokawa [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6,22,5],"tags":[],"class_list":["post-640","post","type-post","status-publish","format-standard","hentry","category-hellraisin","category-nets-n-webs","category-secrets"],"_links":{"self":[{"href":"http:\/\/arxivblog.com\/index.php?rest_route=\/wp\/v2\/posts\/640","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/arxivblog.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/arxivblog.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/arxivblog.com\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"http:\/\/arxivblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=640"}],"version-history":[{"count":0,"href":"http:\/\/arxivblog.com\/index.php?rest_route=\/wp\/v2\/posts\/640\/revisions"}],"wp:attachment":[{"href":"http:\/\/arxivblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=640"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/arxivblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=640"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/arxivblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=640"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}