{"id":4220,"date":"2019-07-01T13:30:10","date_gmt":"2019-07-01T18:30:10","guid":{"rendered":"https:\/\/scottaaronson.blog\/?p=4220"},"modified":"2019-09-24T21:18:17","modified_gmt":"2019-09-25T02:18:17","slug":"quantum-sabinacy","status":"publish","type":"post","link":"https:\/\/scottaaronson.blog\/?p=4220","title":{"rendered":"Quantum Sabinacy"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">Sabine Hossenfelder&#8212;well-known to readers of <em>Shtetl-Optimized<\/em> for <a href=\"https:\/\/scottaaronson.blog\/?p=4122\">opposing the building<\/a> of a higher-energy collider, and various other things&#8212;has weighed in on &#8220;quantum supremacy&#8221; in <a href=\"http:\/\/backreaction.blogspot.com\/2019\/06\/quantum-supremacy-what-is-it-and-what.html?utm_source=feedburner&amp;utm_medium=feed&amp;utm_campaign=Feed:+Backreaction+(Backreaction)&amp;m=1\">this blog post<\/a> and <a href=\"https:\/\/www.youtube.com\/watch?time_continue=1&amp;v=GKnfVA1v5ow\">this video<\/a>.  Sabine consulted with me by phone before doing the video and post, and despite what some might see as her negative stance, I agree with what she has to say substantially more than I disagree.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">I do, however, have a few quibbles:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"> 1. We don\u2019t know that millions of physical qubits will be needed for useful simulations of quantum chemistry.&nbsp; It all depends on how much error correction is needed and how good the error-correcting codes and simulation algorithms become.  Like, sure, you can generate pessimistic forecasts by plugging numbers in to the best known codes and algorithms.  But &#8220;the best known&#8221; is a rapidly moving target&#8212;one where there have already been orders-of-magnitude improvements in the last decade.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">2. To my mind, there\u2019s a big conceptual difference between a single molecule that you can\u2019t efficiently simulate classically, and a programmable computer that you can&#8217;t efficiently simulate classically.&nbsp; The difference, in short, is that only for the computer, and not for the molecule, would it ever make sense to say it had given you a <strong>wrong<\/strong> answer!  In other words, a physical system becomes a &#8220;computer&#8221; when, and only when, you have sufficient understanding of, and control over, its state space and time evolution that you can ask the system to simulate something <em>other than itself<\/em>, and then judge whether it succeeded or failed at that goal.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">3. The entire point of my recent work, on certified randomness generation (see for example <a href=\"https:\/\/www.scottaaronson.com\/talks\/certrand2.ppt\">here<\/a> or <a href=\"https:\/\/www.quantamagazine.org\/how-to-turn-a-quantum-computer-into-the-ultimate-randomness-generator-20190619\/\">here<\/a>), is that sampling random bits with a NISQ-era device <em>could<\/em> have a practical application.  That application is &#8230; I hope you&#8217;re sitting down for this &#8230; sampling random bits!  And then, more importantly and nontrivially, <strong>proving<\/strong> to a faraway skeptic that the bits really were randomly generated.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">4. While I was involved in some of the first proposals for NISQ quantum supremacy experiments (such as <a href=\"https:\/\/en.wikipedia.org\/wiki\/Boson_sampling\">BosonSampling<\/a>), I certainly can\u2019t take sole credit for the idea of quantum supremacy! &nbsp;The term, incidentally, <a href=\"https:\/\/arxiv.org\/abs\/1203.5813\">was coined by John Preskill<\/a>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">5. The term &#8220;NISQ&#8221; (Noisy Intermediate Scale Quantum) was also <a href=\"https:\/\/arxiv.org\/abs\/1801.00862\">coined by John Preskill<\/a>.&nbsp; He had no intention of misleading investors\u2014he just needed a term to discuss the quantum computers that will plausibly be available in the near future.&nbsp; As readers of this blog know, there certainly <em>has<\/em> been some misleading of investors (and journalists, and the public&#8230;) about the applications of near-term QCs.  But I don&#8217;t think you can lay it at the feet of the term \u201cNISQ.\u201d<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Sabine Hossenfelder&#8212;well-known to readers of Shtetl-Optimized for opposing the building of a higher-energy collider, and various other things&#8212;has weighed in on &#8220;quantum supremacy&#8221; in this blog post and this video. Sabine consulted with me by phone before doing the video and post, and despite what some might see as her negative stance, I agree with [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"advanced_seo_description":"","jetpack_seo_html_title":"","jetpack_seo_noindex":false,"jetpack_seo_schema_type":"","_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":[5,4],"tags":[],"class_list":["post-4220","post","type-post","status-publish","format-standard","hentry","category-complexity","category-quantum"],"jetpack_publicize_connections":[],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/scottaaronson.blog\/index.php?rest_route=\/wp\/v2\/posts\/4220","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\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/scottaaronson.blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=4220"}],"version-history":[{"count":5,"href":"https:\/\/scottaaronson.blog\/index.php?rest_route=\/wp\/v2\/posts\/4220\/revisions"}],"predecessor-version":[{"id":4228,"href":"https:\/\/scottaaronson.blog\/index.php?rest_route=\/wp\/v2\/posts\/4220\/revisions\/4228"}],"wp:attachment":[{"href":"https:\/\/scottaaronson.blog\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=4220"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/scottaaronson.blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=4220"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/scottaaronson.blog\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=4220"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}