{"pk":65017,"title":"On the face stratification of the \\(m=2\\) amplituhedron","subtitle":null,"abstract":"We define and study the face stratification of the \\(m=2\\) amplituhedron. We show that the face poset is an upper order ideal in the face poset of the totally nonnegative Grassmannian. Our construction is consistent with earlier work of Lukowski, and we confirm various predictions of Lukowski.\n \nMathematics Subject Classifications: 05E14, 52B40\n \nKeywords: Total positivity, amplituhedron, Grassmannian","language":"en","license":{"name":"Creative Commons Attribution 4.0","short_name":"CC BY 4.0","text":"Attribution — You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.\n\nNo additional restrictions — You may not apply legal terms or technological measures that legally restrict others from doing anything the license permits.","url":"https://creativecommons.org/licenses/by/4.0"},"keywords":[{"word":"Total positivity"},{"word":"amplituhedron"},{"word":"Grassmannian"}],"section":"Research Articles","is_remote":true,"remote_url":"https://escholarship.org/uc/item/890692zw","frozenauthors":[{"first_name":"Thomas","middle_name":"","last_name":"Lam","name_suffix":"","institution":"Department of Mathematics, University of Michigan, 2074 East Hall, 530 Church Street, Ann Arbor, MI 48109-1043, U.S.A.","department":""}],"date_submitted":"2026-02-02T08:56:07Z","date_accepted":"2026-02-02T08:56:07Z","date_published":"2025-12-20T08:00:00Z","render_galley":null,"galleys":[{"label":"","type":"pdf","path":"https://journalpub.escholarship.org/combinatorial_theory/article/65017/galley/49827/download/"}]}