{ "151803-21912195": { "datetime_modified":"20261022T130355", "datetime_start":"20261023T150000", "datetime_end":"20261023T160000", "has_end_time":1, "date_start":"2026-10-23", "date_end":"2026-10-23", "time_start":"15:00:00", "time_end":"16:00:00", "time_zone":"America\/Detroit", "event_title":"HET Seminar | Dark Energy and Time Reparametrizations", "occurrence_title":"", "combined_title":"HET Seminar | Dark Energy and Time Reparametrizations: Jun Nian (ICTP-AP)", "event_subtitle":"Jun Nian (ICTP-AP)", "event_type":"Lecture \/ Discussion", "event_type_id":"13", "description":"***Please note: Due to unforeseen circumstances, this seminar has been CANCELLED***\n\nThe cosmological constant\u2019s quantum origin is a famous open problem in theoretical physics and cosmology. Its observed value and theoretical prediction exhibit a large 120-order discrepancy. In this talk, we first summarize the current state of research on the cosmological constant problem and review the Schwarzian theory of time reparametrizations in the literature. Inspired by an early work by Gary Gibbons and our recent attempts to solve various formidable problems (e.g., color confinement in SYM, fluid\/gravity correspondence at low temperatures, etc.) via the JT gravity\/Schwarzian theory duality, we apply the Schwarzian theory of time reparametrizations and its ensemble average to the cosmological constant problem and propose a new approach to resolving it. We will show that this new method, at leading order, yields a theoretical value that exactly matches the observed value of the cosmological constant. However, recent results from dark energy observations (such as DESI) suggest a dynamical dark energy. Starting from the leading-order constant value, we will take into account matter-gravity interactions and develop a more realistic dynamical dark energy model based on time reparametrizations that can fit observational data with comparable precision to other models (e.g., LCDM and CPL). We also provide some falsifiable predictions for future more precise observations. This talk is based on my recent paper arXiv:2602.17476 and another upcoming work.\n\nBrief Biography:\nJun Nian is an assistant professor at the International Centre for Theoretical Physics Asia-Pacific (ICTP-AP), University of Chinese Academy of Sciences. He received a Diplom degree from the University of Heidelberg in 2009 and a Ph.D. degree from Stony Brook University in 2015. Before joining ICTP-AP in 2021, he was a postdoctoral fellow at Institut des Hautes Etudes Scientifiques (IHES), the University of Michigan, and the University of Milan. His research interests include quantum field theory, gravity theory, and string theory, with a recent focus on the quantum-gravitational effects in black holes and cosmology.", "occurrence_notes":null, "guid":"151803-21912195@events.umich.edu", "permalink":"http:\/\/events.umich.edu\/event\/151803", "building_id":"1000208", "building_name":"Randall Laboratory", "campus_maps_id":"133", "room":"4404", "location_name":"Randall Laboratory", "has_livestream":0, "cost":"", "tags":["Talk","High Energy Theory Seminar","Lecture","Physics","Science","Seminar"], "website":"", "sponsors":[ { "group_name":"Leinweber Institute for Theoretical Physics", "group_id":"4286", "website":"" }, { "group_name":"Department of Physics", "group_id":"1965", "website":"" }, { "group_name":"HET Seminars", "group_id":"3806", "website":"" }, { "group_name":"Leinweber Institute for Theoretical Physics Seminars", "group_id":"4311", "website":"" }, { "group_name":"Leinweber Institute for Theoretical Physics High Energy Theory Seminars", "group_id":"4313", "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":21912195 } , "148332-21903935": { "datetime_modified":"20261020T144533", "datetime_start":"20261023T150000", "datetime_end":"20261023T163000", "has_end_time":1, "date_start":"2026-10-23", "date_end":"2026-10-23", "time_start":"15:00:00", "time_end":"16:30:00", "time_zone":"America\/Detroit", "event_title":"Incorporations: Capitalism and Collective Life with Associate Professor Matthew Hull", "occurrence_title":"", "combined_title":"Incorporations: Capitalism and Collective Life with Associate Professor Matthew Hull: U-M Anthropology 2026 Roy A. Rappaport Lecture Series", "event_subtitle":"U-M Anthropology 2026 Roy A. Rappaport Lecture Series", "event_type":"Lecture \/ Discussion", "event_type_id":"13", "description":"Join the U-M Department of Anthropology for the annual Roy A. Rappaport Lecture Series! Associate Professor Matthew Hull will present the fall 2026 series, titled \u201cIncorporations: Capitalism and Collective Life.\u201d\n\nAbstract: \u201cCorporations are often seen as purely economic actors, but they have been central to Anglo-American governance for centuries\u2014pioneers of democratic assembly, speech, citizenship, and constitutions. Many features of corporations, once grounded in democratic ideals, now foster the unresponsiveness of these institutions. These lectures will include discussion of a diverse array of corporations: medieval guilds, the English East India Company, Alaska Native corporations, and caste-based corporations in India.\u201d\n\nRappaport lectures will take place on the following fall Fridays from 3 to 4:30 p.m. in West Hall Room 411. They are free and open to the public:\n\nFriday, Sept. 25\n\u201cCorporate Persons in Human Law: Reproduction, Kinship, Jurisdiction\u201d\n\nFriday, Oct. 23\n\u201cFreedom and Citizenship: Corporate Membership and the Making of Exclusion\u201d\n\nFriday, Nov. 13\n\u201cMeetings and Speech: Corporate Mediations of Will\u201d\n\nFriday, Dec. 4\n\u201cSharing and Inequality in Corporations\u201d\n\nVIRTUAL PARTICIPATION LINK: https:\/\/umich.zoom.us\/j\/91475190155\n\nREGISTRATION IS APPRECIATED for planning purposes: https:\/\/myumi.ch\/e77Ax\n\nIf you need accommodations to attend, please email anthro.exec.secretary@umich.edu.\n\nABOUT ASSOCIATE PROFESSOR MATTHEW HULL\nMatthew Hull is Associate Professor of Anthropology at the University of Michigan. His research focuses on the nexus of signification, technology, and institutions. His book, \u201cGovernment of Paper: The Materiality of Bureaucracy in Urban Pakistan,\u201d winner of the 2019 J.I. Staley Prize from the School of Advanced Research, examines governance as a semiotic and material practice. He has worked on urban planning in 1960s India and police communication systems and lotteries in contemporary India. He is currently writing a book on how early modern corporations shaped democratic governance and continue to structure contemporary political life.", "occurrence_notes":null, "guid":"148332-21903935@events.umich.edu", "permalink":"http:\/\/events.umich.edu\/event\/148332", "building_id":"1000167", "building_name":"West Hall", "campus_maps_id":"163", "room":"411", "location_name":"West Hall", "has_livestream":0, "cost":"", "tags":["South Asian Studies","Lecture","Anthropology","AEM Featured"], "website":"https:\/\/lsa.umich.edu\/anthro", "sponsors":[ { "group_name":"Department of Anthropology", "group_id":"3469", "website":"https:\/\/lsa.umich.edu\/anthro" }, { "group_name":"Center for South Asian Studies", "group_id":"3273", "website":"http:\/\/www.ii.umich.edu\/csas" }, { "group_name":"Museum of Anthropological Archaeology", "group_id":"3760", "website":"" } ], "image_url":"https:\/\/events.umich.edu\/media\/attachments\/2026\/08\/event_148332_original-2.png", "styled_images":{ "event_thumb":"https:\/\/events.umich.edu\/media\/cache\/event_thumb\/media\/attachments\/2026\/08\/crop-event_148332_original-2.png", "event_large":"https:\/\/events.umich.edu\/media\/cache\/event_large\/media\/attachments\/2026\/08\/crop-event_148332_original-2.png", "event_large_2x":"https:\/\/events.umich.edu\/media\/cache\/event_large_2x\/media\/attachments\/2026\/08\/crop-event_148332_original-2.png", "event_large_lightbox":"https:\/\/events.umich.edu\/media\/cache\/event_large_lightbox\/media\/attachments\/2026\/08\/crop-event_148332_original-2.png", "group_thumb":"https:\/\/events.umich.edu\/media\/cache\/group_thumb\/media\/attachments\/2026\/08\/crop-event_148332_original-2.png", "group_thumb_square":"https:\/\/events.umich.edu\/media\/cache\/group_thumb_square\/media\/attachments\/2026\/08\/crop-event_148332_original-2.png", "group_large":"https:\/\/events.umich.edu\/media\/cache\/group_large\/media\/attachments\/2026\/08\/crop-event_148332_original-2.png", "group_large_lightbox":"https:\/\/events.umich.edu\/media\/cache\/group_large_lightbox\/media\/attachments\/2026\/08\/crop-event_148332_original-2.png", "event_large_crop":"https:\/\/events.umich.edu\/media\/cache\/event_large_crop\/media\/attachments\/2026\/08\/crop-event_148332_original-2.png", "event_list":"https:\/\/events.umich.edu\/media\/cache\/event_list\/media\/attachments\/2026\/08\/crop-event_148332_original-2.png", "event_list_2x":"https:\/\/events.umich.edu\/media\/cache\/event_list_2x\/media\/attachments\/2026\/08\/crop-event_148332_original-2.png", "event_grid":"https:\/\/events.umich.edu\/media\/cache\/event_grid\/media\/attachments\/2026\/08\/crop-event_148332_original-2.png", "event_grid_2x":"https:\/\/events.umich.edu\/media\/cache\/event_grid_2x\/media\/attachments\/2026\/08\/crop-event_148332_original-2.png", "event_feature_large":"https:\/\/events.umich.edu\/media\/cache\/event_feature_large\/media\/attachments\/2026\/08\/crop-event_148332_original-2.png", "event_feature_thumb":"https:\/\/events.umich.edu\/media\/cache\/event_feature_thumb\/media\/attachments\/2026\/08\/crop-event_148332_original-2.png" }, "occurrence_count":4, "first_occurrence":21903934 } }