{"paper":{"title":"Fermion Mass Hierarchy in the Grand Unified Theory on $S_1/(Z_2 \\times Z_2')$ Orbifold","license":"","headline":"","cross_cats":[],"primary_cat":"hep-ph","authors_text":"Kazumasa Ukai, N. Haba, Tomoharu Suzuki, Y. Shimizu","submitted_at":"2001-07-17T11:20:57Z","abstract_excerpt":"We suggest a simple grand unified theory where the fifth dimensional coordinate is compactified on an $S_1/(Z_2 \\times Z_2')$ orbifold. This model is based on the supersymmetric flipped $SU(5) \\times U(1)$ grand unified theory, which can realize not only the triplet-doublet splitting but also the natural fermion mass hierarchies. The triplet-doublet splitting is realized by $S_1/(Z_2 \\times Z_2')$ orbifolding, which also reduces the gauge group as $SU(5) \\times U(1) \\to SU(3)_c \\times SU(2)_L \\times U(1)_Z \\times U(1)_X$. The suitable fermion mass hierarchies are generated by integrating out e"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"hep-ph/0107190","kind":"arxiv","version":4},"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"}