{"id":4106,"date":"2011-11-03T16:01:25","date_gmt":"2011-11-03T20:01:25","guid":{"rendered":"http:\/\/www.math.columbia.edu\/~woit\/wordpress\/?p=4106"},"modified":"2011-11-03T21:53:53","modified_gmt":"2011-11-04T01:53:53","slug":"recollections-of-rudolf-haag","status":"publish","type":"post","link":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/?p=4106","title":{"rendered":"Recollections of Rudolf Haag"},"content":{"rendered":"

Thomas Love pointed me to a wonderful article from last year by Rudolf Haag. It’s more or less a short memoir of his scientific career, entitled Some people and some problems met in half a century of commitment to mathematical physics<\/a>. There’s a lot about the history of mathematical physics related to quantum field theory that I learned from the article, which covers the second half of the twentieth century. Haag started out his career heavily influenced by Wigner and his work on representations of the Poincaré group, investigating what this had to do with quantum field theory. He has been one of the leaders of the operator algebra approach to formulating QFT.<\/p>\n

His comments about the Witten and string theory bring back memories of the late eighties, when several people told me of similar experiences. Haag writes:<\/p>\n

\nI had been asked to give a physics colloquium talk about my views on quantum gravity and hoped to have some discussion with Ed Witten. Next morning he greeted me by saying: \u201cYour talk was very interesting but I would really advise you to work on string theory\u201d. When he saw the somewhat incredulous look on my face he added \u201cI really mean it. I shall send you the manuscript of the first chapters of our book\u201d. This ended our discussion. Back in Hamburg I received the manuscript but it did not convert me to string theory. I remained a heathen to this day and regret that meanwhile most physics departments believe that they must have a string theory group and have filled their vacant positions with string theorists. To be precise: It is good that people with vision like Ed Witten spend time trying to develop a revolutionary theory. But it is not healthy if a whole generation of young theorists is engaged in speculative work with only superficial grounding in traditional knowledge. In many popularised presentations the starting point of string theory is explained as the replacement of the fundamental notion of \u201cparticles\u201d with its classical picture of a point in space or a world line in space-time by a string in space respectively a two-dimensional worldsheet in space-time. This, I think, is a misunderstanding of existing wisdom. First of all, paraphrasing Heisenberg, one may say \u201cParticles are the roof of the theory, not its foundation\u201d.<\/p><\/blockquote>\n","protected":false},"excerpt":{"rendered":"

Thomas Love pointed me to a wonderful article from last year by Rudolf Haag. It’s more or less a short memoir of his scientific career, entitled Some people and some problems met in half a century of commitment to mathematical … Continue reading →<\/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-4106","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\/4106","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=4106"}],"version-history":[{"count":6,"href":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/4106\/revisions"}],"predecessor-version":[{"id":4117,"href":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/4106\/revisions\/4117"}],"wp:attachment":[{"href":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=4106"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=4106"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=4106"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}