{"paper":{"title":"On a question of Hof, Knill and Simon on palindromic substitutive systems","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["math.CO"],"primary_cat":"math.DS","authors_text":"Jetro Vesti, Luca Q. Zamboni, Tero Harju","submitted_at":"2013-11-01T13:55:04Z","abstract_excerpt":"In a 1995 paper, Hof, Knill and Simon obtain a sufficient combinatorial criterion on the hull $\\Omega$ of the potential of a discrete Schr\\\"odinger operator which guarantees purely singular continuous spectrum on a generic subset of $\\Omega.$ In part, this condition requires the existence of infinitely many palindromic factors. In this same paper, they introduce the class P of morphisms $f:A^*\\rightarrow B^*$ of the form $a\\mapsto pq_a$ and ask whether every palindromic subshift generated by a primitive substitution arises from morphisms of class P or by morphisms of the form $a\\mapsto q_ap$ w"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1311.0185","kind":"arxiv","version":2},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}