{ "132741-21871669": { "datetime_modified":"20250307T100011", "datetime_start":"20250313T143000", "datetime_end":"20250313T163000", "has_end_time":1, "date_start":"2025-03-13", "date_end":"2025-03-13", "time_start":"14:30:00", "time_end":"16:30:00", "time_zone":"America\/Detroit", "event_title":"Dissertation Defense: Log-Determinant of the Laguerre Beta Ensembles and Free Energy of the Bipartite Spherical Sherrington\u2013Kirkpatrick Model", "occurrence_title":"", "combined_title":"Dissertation Defense: Log-Determinant of the Laguerre Beta Ensembles and Free Energy of the Bipartite Spherical Sherrington\u2013Kirkpatrick Model: Han Le", "event_subtitle":"Han Le", "event_type":"Presentation", "event_type_id":"16", "description":"Abstract:\r\n\r\nThis thesis consists of two parts, each addressing a distinct problem concerning the asymptotic behavior of large disordered systems. The first part studies random matrices from the Laguerre beta ensembles. We prove that when a Laguerre matrix is shifted by a scalar multiple of the identity\u2014where the scalar is near the edge of the Mar\\v{c}enko\u2013Pastur law\u2014the logarithm of its determinant exhibits Gaussian fluctuations. Additionally, we establish that this result extends to the Laguerre Orthogonal and Laguerre Unitary Ensembles under a relaxed assumption on the shift. This edge central limit theorem has applications in statistical testing of critically spiked sample covariance matrices, and in analyzing free energy fluctuations of bipartite spherical spin glasses at critical temperature. The second part examines the free energy fluctuations of the bipartite spherical Sherrington\u2013Kirkpatrick model, an extension of the spherical Sherrington\u2013Kirkpatrick model by incorporating heterogeneity. Previous work by Baik and Lee shows that at non-critical temperatures, the free energy exhibits Gaussian fluctuations at high temperatures and Tracy\u2013Widom fluctuations at low temperatures. We focus on the critical temperature case and demonstrate that within a vanishing window around criticality, the fluctuations are given by the sum of independent Gaussian and Tracy\u2013Widom random variables. A key component of our analysis is the central limit theorem for Laguerre matrices established in the first part of the thesis.", "occurrence_notes":null, "guid":"132741-21871669@events.umich.edu", "permalink":"http:\/\/events.umich.edu\/event\/132741", "building_id":"1000221", "building_name":"School of Education", "campus_maps_id":"136", "room":"2310", "location_name":"School of Education", "has_livestream":1, "livestream_type":"zoom", "livetream_require_login":0, "livestream_id":"99770476459", "livestream_password":"Please contact math-grad-office@umich.edu for password", "livestream_link":"https:\/\/umich.zoom.us\/j\/99770476459", "cost":"", "tags":["Dissertation","Graduate","Graduate Students","Mathematics"], "website":"", "sponsors":[ { "group_name":"Dissertation Defense - Department of Mathematics", "group_id":"4889", "website":"" }, { "group_name":"Department of Mathematics", "group_id":"3791", "website":"" } ], "image_url":"https:\/\/events.umich.edu\/media\/attachments\/2025\/03\/event_132741_original-2.jpg", "styled_images":{ "event_thumb":"https:\/\/events.umich.edu\/media\/cache\/resolve\/event_thumb\/media\/attachments\/2025\/03\/event_132741_original-2.jpg", "event_large":"https:\/\/events.umich.edu\/media\/cache\/event_large\/media\/attachments\/2025\/03\/event_132741_original-2.jpg", "event_large_2x":"https:\/\/events.umich.edu\/media\/cache\/event_large_2x\/media\/attachments\/2025\/03\/event_132741_original-2.jpg", "event_large_lightbox":"https:\/\/events.umich.edu\/media\/cache\/event_large_lightbox\/media\/attachments\/2025\/03\/event_132741_original-2.jpg", "group_thumb":"https:\/\/events.umich.edu\/media\/cache\/resolve\/group_thumb\/media\/attachments\/2025\/03\/event_132741_original-2.jpg", "group_thumb_square":"https:\/\/events.umich.edu\/media\/cache\/resolve\/group_thumb_square\/media\/attachments\/2025\/03\/event_132741_original-2.jpg", "group_large":"https:\/\/events.umich.edu\/media\/cache\/resolve\/group_large\/media\/attachments\/2025\/03\/event_132741_original-2.jpg", "group_large_lightbox":"https:\/\/events.umich.edu\/media\/cache\/resolve\/group_large_lightbox\/media\/attachments\/2025\/03\/event_132741_original-2.jpg", "event_large_crop":"https:\/\/events.umich.edu\/media\/cache\/resolve\/event_large_crop\/media\/attachments\/2025\/03\/event_132741_original-2.jpg", "event_list":"https:\/\/events.umich.edu\/media\/cache\/resolve\/event_list\/media\/attachments\/2025\/03\/event_132741_original-2.jpg", "event_list_2x":"https:\/\/events.umich.edu\/media\/cache\/event_list_2x\/media\/attachments\/2025\/03\/event_132741_original-2.jpg", "event_grid":"https:\/\/events.umich.edu\/media\/cache\/event_grid\/media\/attachments\/2025\/03\/event_132741_original-2.jpg", "event_grid_2x":"https:\/\/events.umich.edu\/media\/cache\/resolve\/event_grid_2x\/media\/attachments\/2025\/03\/event_132741_original-2.jpg", "event_feature_large":"https:\/\/events.umich.edu\/media\/cache\/resolve\/event_feature_large\/media\/attachments\/2025\/03\/event_132741_original-2.jpg", "event_feature_thumb":"https:\/\/events.umich.edu\/media\/cache\/resolve\/event_feature_thumb\/media\/attachments\/2025\/03\/event_132741_original-2.jpg" }, "occurrence_count":1, "first_occurrence":21871669 } , "133439-21873101": { "datetime_modified":"20250305T081707", "datetime_start":"20250313T143000", "datetime_end":"20250313T153000", "has_end_time":1, "date_start":"2025-03-13", "date_end":"2025-03-13", "time_start":"14:30:00", "time_end":"15:30:00", "time_zone":"America\/Detroit", "event_title":"Special Interdisciplinary QC-CM Seminar | Quantum active solids: Photoinduced non-reciprocal magnetism", "occurrence_title":"", "combined_title":"Special Interdisciplinary QC-CM Seminar | Quantum active solids: Photoinduced non-reciprocal magnetism: Ryo Hanai (YITP)", "event_subtitle":"Ryo Hanai (YITP)", "event_type":"Workshop \/ Seminar", "event_type_id":"21", "description":"Out of equilibrium, the action-reaction symmetry of the interactions is often broken, leading to the emergence of various collective phenomena with no equilibrium counterparts. Although ubiquitous in classical active systems, implementing such non-reciprocal interactions in solid-state systems has remained challenging, as the known quantum schemes require precise control over the system on a single-site level. Here, we propose a novel dissipation-engineering protocol to induce non-reciprocal interactions in solid-state platforms with light, which we expect to be achievable with state-of the-art experimental techniques. Focusing on magnetic metals for concreteness, we show microscopically that a light injection that introduces the decay channel to a virtually excited state gives rise to non-reciprocal interactions between localized spins. One can even realize a situation where spin A tries to align with spin B but the B tries the opposite, resulting in chase-and-runaway dynamics. Applying our scheme to layered ferromagnets, we show that a non-reciprocal phase transition from a static to a many-body time-dependent chiral phase emerges. Our work paves the way to bring solid-state systems to the realm of non-reciprocal science, providing yet another possibility to control quantum matter with light.", "occurrence_notes":null, "guid":"133439-21873101@events.umich.edu", "permalink":"http:\/\/events.umich.edu\/event\/133439", "building_id":"1000167", "building_name":"West Hall", "campus_maps_id":"163", "room":"335", "location_name":"West Hall", "has_livestream":0, "cost":"", "tags":["Physics","Science"], "website":"", "sponsors":[ { "group_name":"Interdisciplinary QC\/CM Seminars", "group_id":"3811", "website":"" }, { "group_name":"Department of Physics", "group_id":"1965", "website":"" } ], "image_url":"", "styled_images":{ "event_thumb":"", "event_large":"", "event_large_2x":"", "event_large_lightbox":"", "group_thumb":"", "group_thumb_square":"", "group_large":"", "group_large_lightbox":"", "event_large_crop":"", "event_list":"", "event_list_2x":"", "event_grid":"", "event_grid_2x":"", "event_feature_large":"", "event_feature_thumb":"" }, "occurrence_count":1, "first_occurrence":21873101 } }