{"id":53460,"date":"2025-08-20T08:38:55","date_gmt":"2025-08-20T12:38:55","guid":{"rendered":"https:\/\/engineering.jhu.edu\/ams\/?post_type=tribe_events&#038;p=53460"},"modified":"2025-10-13T10:56:52","modified_gmt":"2025-10-13T14:56:52","slug":"ams-weekly-seminar-joel-tropp","status":"publish","type":"tribe_events","link":"https:\/\/engineering.jhu.edu\/ams\/event\/ams-weekly-seminar-joel-tropp\/","title":{"rendered":"AMS Special Seminar Series | Joel Tropp"},"content":{"rendered":"<p><strong>Location: <\/strong>Krieger 205<\/p>\n<p><strong>When:<\/strong> October 16th at 1:30 p.m.<\/p>\n<p><strong>Title: <\/strong>Positive Random Walks and Positive-Semidefinite Random Matrices<\/p>\n<p><strong>Abstract:<\/strong>\u00a0On the real line, a random walk that can only move in the positive direction is very unlikely to remain close to its starting point. After a fixed number of steps, the left tail has a Gaussian profile, under minimal assumptions. Remarkably, the same phenomenon occurs when we consider a positive random walk on the cone of positive-semidefinite matrices. After a fixed number of steps, the minimum eigenvalue is also described by a Gaussian model.<\/p>\n<p>This talk introduces a new way to make this intuition rigorous. The methodology provides the solution to an open problem in computational mathematics about sparse random embeddings. The presentation is targeted at a general mathematical audience.<\/p>\n<p>Preprint:\u00a0<a href=\"https:\/\/nam02.safelinks.protection.outlook.com\/?url=https%3A%2F%2Farxiv.org%2Fabs%2F2501.16578&amp;data=05%7C02%7Csfitzg21%40jhu.edu%7C5e13d5d302ab41ce60fb08de05bb3719%7C9fa4f438b1e6473b803f86f8aedf0dec%7C0%7C0%7C638954498795939492%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&amp;sdata=X0mguDDs4RNX00tJSxrDIJstzEvZQw2j06tQSJcJPTo%3D&amp;reserved=0\" data-outlook-id=\"f87a795e-0683-447f-b21c-05c45c153411\">https:\/\/arxiv.org\/abs\/2501.16578<\/a><\/p>\n<p><strong>Zoom link:<\/strong> <a href=\"https:\/\/wse.zoom.us\/j\/93600407710?pwd=JBL8VsObRxX6MkhdjAUxCadqJDoZrZ.1\">https:\/\/wse.zoom.us\/j\/93600407710?pwd=JBL8VsObRxX6MkhdjAUxCadqJDoZrZ.1<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Location: Krieger 205 When: October 16th at 1:30 p.m. Title: Positive Random Walks and Positive-Semidefinite Random Matrices Abstract:\u00a0On the real line, a random walk that can only move in the&hellip;<\/p>\n","protected":false},"author":69,"featured_media":0,"template":"","meta":{"_acf_changed":false,"_relevanssi_hide_post":"","_relevanssi_hide_content":"","_relevanssi_pin_for_all":"","_relevanssi_pin_keywords":"","_relevanssi_unpin_keywords":"","_relevanssi_related_keywords":"","_relevanssi_related_include_ids":"","_relevanssi_related_exclude_ids":"","_relevanssi_related_no_append":"","_relevanssi_related_not_related":"","_relevanssi_related_posts":"","_relevanssi_noindex_reason":"","_tribe_events_status":"","_tribe_events_status_reason":"","footnotes":""},"tags":[],"tribe_events_cat":[260],"class_list":["post-53460","tribe_events","type-tribe_events","status-publish","hentry","tribe_events_cat-seminars-and-endowed-lectures","cat_seminars-and-endowed-lectures"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.8 - 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