{"id":377,"date":"2009-01-09T12:50:56","date_gmt":"2009-01-09T16:50:56","guid":{"rendered":"https:\/\/scottaaronson.blog\/?p=377"},"modified":"2009-01-09T12:50:56","modified_gmt":"2009-01-09T16:50:56","slug":"the-t-vs-ht-truth-vs-higher-truth-problem","status":"publish","type":"post","link":"https:\/\/scottaaronson.blog\/?p=377","title":{"rendered":"The T vs. HT (Truth vs. Higher Truth) problem"},"content":{"rendered":"<p>From a <a href=\"http:\/\/www.ams.org\/notices\/200902\/rtx090200212p.pdf\">predictably-interesting article<\/a> by Freeman Dyson in <em>Notices of the AMS<\/em> (hat tip to <a href=\"http:\/\/www.math.columbia.edu\/~woit\/wordpress\/?p=1506\">Peter Woit<\/a>):<\/p>\n<blockquote><p>The mathematicians discovered the central mystery of computability, the conjecture represented by the statement P is not equal to NP. The conjecture asserts that there exist mathematical problems which can be quickly solved in individual cases but cannot be solved by a quick algorithm applicable to all cases. The most famous example of such a problem is the traveling salesman problem, which is to find the shortest route for a salesman visiting a set of cities, knowing the distance between each pair. All the experts believe that the conjecture is true, and that the traveling salesman problem is an example of a problem that is P but not NP. But nobody has even a glimmer of an idea how to prove it. This is a mystery that could not even have been formulated within the nineteenth-century mathematical universe of Hermann Weyl.<\/p><\/blockquote>\n<p>At a literal level, the above passage contains several howlers (I&#8217;ll leave it to commenters to point them out), but at a &#8220;deeper&#8221; &#8220;poetic&#8221; level, Dyson happens to be absolutely right: P versus NP is the example <em>par excellence<\/em> of a mathematical mystery that human beings lacked the language even to express until very recently in our history.<\/p>\n<p>Speaking of P versus NP, I&#8217;m currently visiting <a href=\"http:\/\/www.mi.ras.ru\/~razborov\/\">Sasha Razborov<\/a> at his new home, the University of Chicago.\u00a0 (Yesterday we had lunch at &#8220;Barack&#8217;s favorite pizza place&#8221;, and walked past &#8220;Barack&#8217;s favorite bookstore.&#8221;\u00a0 Were they <em>really<\/em> his favorites?\u00a0 At a deeper poetic level, sure.)<\/p>\n<p>One of the highlights of my trip was meeting <a href=\"http:\/\/ramakrishnadas.cs.uchicago.edu\/\">Ketan Mulmuley<\/a> for the first time, and talking with him about his <a href=\"http:\/\/ramakrishnadas.cs.uchicago.edu\/gctabs.ps\">geometric approach<\/a> to the P vs. NP problem.\u00a0 Ketan comes across in person as an almost mythological figure, like a man who flew too close to the sun and was driven nearly to ecstatic obsession by what he saw.\u00a0 This is someone who&#8217;ll explain to anyone in earshot, for as long as he or she cares to listen, that he&#8217;s glimpsed the outlines of a solution of the P vs. NP problem in the far frontiers of mathematics, and it is beautiful, and it is elegant&#8212;someone who leaps from Ramanujan graphs to quantum groups to the Riemann Hypothesis over finite fields to circuit lower bounds in the space of a single sentence, as his hapless listener struggles to hold on by a fingernail&#8212;someone whose ideas seem to remain obstinately in limbo between incoherence and profundity, making just enough sense that you keep listening to them.<\/p>\n<p>Now, I get emails every few months from people claiming to have proved P\u2260NP (not even counting the P=NP claimants).\u00a0 Without exception, they turn out to be hunting polar bears in the Sahara: they don&#8217;t even grapple with natural proofs, or relativization, or algebrization, or the lower bounds\/derandomization connection, or any the other stuff we know already about why the problem is hard.\u00a0 Ketan, by contrast, might be searching for polar bears with a kaleidoscope and trying to hunt them with a feather, but he&#8217;s in the Arctic all right.\u00a0 I have no idea whether his program will succeed within my lifetime at uncovering any of the truth about the P vs. NP problem, but it at least clears the lower hurdle of reflecting some of the higher truth.<\/p>\n<p><input id=\"gwProxy\" type=\"hidden\" \/><!--Session data--><input onclick=\"jsCall();\" id=\"jsProxy\" type=\"hidden\" \/><\/p>\n","protected":false},"excerpt":{"rendered":"<p>From a predictably-interesting article by Freeman Dyson in Notices of the AMS (hat tip to Peter Woit): The mathematicians discovered the central mystery of computability, the conjecture represented by the statement P is not equal to NP. The conjecture asserts that there exist mathematical problems which can be quickly solved in individual cases but cannot [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"advanced_seo_description":"","jetpack_seo_html_title":"","jetpack_seo_noindex":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"{title}\n\n{excerpt}\n\n{url}","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2},"_wpas_customize_per_network":false,"jetpack_post_was_ever_published":false},"categories":[10,5,30],"tags":[],"class_list":["post-377","post","type-post","status-publish","format-standard","hentry","category-adventures-in-meatspace","category-complexity","category-mirrored-on-csail-blog"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/scottaaronson.blog\/index.php?rest_route=\/wp\/v2\/posts\/377","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/scottaaronson.blog\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/scottaaronson.blog\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/scottaaronson.blog\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/scottaaronson.blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=377"}],"version-history":[{"count":1,"href":"https:\/\/scottaaronson.blog\/index.php?rest_route=\/wp\/v2\/posts\/377\/revisions"}],"predecessor-version":[{"id":835,"href":"https:\/\/scottaaronson.blog\/index.php?rest_route=\/wp\/v2\/posts\/377\/revisions\/835"}],"wp:attachment":[{"href":"https:\/\/scottaaronson.blog\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=377"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/scottaaronson.blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=377"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/scottaaronson.blog\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=377"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}