{"id":4572,"date":"2012-04-12T14:38:07","date_gmt":"2012-04-12T18:38:07","guid":{"rendered":"http:\/\/www.math.columbia.edu\/~woit\/wordpress\/?p=4572"},"modified":"2012-04-13T07:20:36","modified_gmt":"2012-04-13T11:20:36","slug":"testing-the-holographic-principle","status":"publish","type":"post","link":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/?p=4572","title":{"rendered":"Testing the Holographic Principle"},"content":{"rendered":"<p>Adrian Cho at Science magazine this week has an <a href=\"http:\/\/www.sciencemag.org\/content\/336\/6078\/147.full.pdf\">article<\/a> about Craig Hogan&#8217;s project to build a &#8220;holometer&#8221; and somehow test the &#8220;holographic principle&#8221;.   Since this promises some sort of experimental test of fashionable ideas about quantum gravity, it has gotten a lot of attention, including a <a href=\"http:\/\/www.scientificamerican.com\/article.cfm?id=is-space-digital\">cover story<\/a> in the February Scientific American (also available <a href=\"http:\/\/www.nature.com\/scientificamerican\/journal\/v306\/n2\/full\/scientificamerican0212-30.html\">here<\/a> and maybe elsewhere).<\/p>\n<p>This kind of thing often gets promoted as a &#8220;test of string theory&#8221;, but in this case, at least from certain quarters, that definitely isn&#8217;t happening.  Cho quotes Raphael Bousso:<\/p>\n<blockquote><p>But some experts on the holographic principle think the experiment is completely off-target. \u201cThere is no relationship between the argument [Hogan] is making and the holographic principle,\u201d Bousso says. \u201cNone whatsoever. Zero.\u201d The problem lies not in Hogan&#8217;s interpretation of the uncertainty relationship, but rather in \u201cthe first step of his analysis,\u201d Bousso contends.<\/p>\n<p>Bousso notes that a premise of special relativity called Lorentz invariance says the rules of physics should be the same for all observers, regardless of how they are moving relative to one another. The holographic principle maintains Lorentz invariance, Bousso says. But Hogan&#8217;s uncertainty formula does not, he argues: An observer standing in the lab and another zipping past would not agree on how much an interferometer&#8217;s beam splitter jitters. So Hogan&#8217;s uncertainty relationship cannot follow from the holographic principle, Bousso argues.<\/p>\n<p>The experiment can do no good in testing the holographic principle, Bousso says, but running it could do plenty of harm. The holometer has garnered an inordinate amount of attention in the blogosphere and in press accounts, he says, raising unrealistic expectations. \u201cThey&#8217;re not going to have a signal and then there is going to be a backlash saying that the holographic principle isn&#8217;t valid, and we&#8217;ll look like we&#8217;re on the defensive,\u201d Bousso says. \u201cThat&#8217;s why I&#8217;m trying to get the word out [that the experiment won&#8217;t test the principle] without appearing to make excuses.\u201d <\/p><\/blockquote>\n<p>There&#8217;s also the following from Lenny Susskind:<\/p>\n<blockquote><p>Not everyone cheers the effort, however. In fact, Leonard Susskind, a theorist at Stanford University in Palo Alto, California, and co-inventor of the holographic principle, says the experiment has nothing to do with his brainchild. \u201cThe idea that this tests anything of interest is silly,\u201d he says, before refusing to elaborate and abruptly hanging up the phone. <\/p><\/blockquote>\n","protected":false},"excerpt":{"rendered":"<p>Adrian Cho at Science magazine this week has an article about Craig Hogan&#8217;s project to build a &#8220;holometer&#8221; and somehow test the &#8220;holographic principle&#8221;. Since this promises some sort of experimental test of fashionable ideas about quantum gravity, it has &hellip; <a href=\"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/?p=4572\">Continue reading <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[1],"tags":[],"class_list":["post-4572","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/4572","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=4572"}],"version-history":[{"count":3,"href":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/4572\/revisions"}],"predecessor-version":[{"id":4575,"href":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/4572\/revisions\/4575"}],"wp:attachment":[{"href":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=4572"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=4572"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=4572"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}