{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"31b24652e415d6cd17f2aaff2820cc399ebf2a5f39806712e90a37511db06045","created":"2026-10-03T07:18:05Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"e917aacd56002b8d6ad00e36df7b32eb151534c7b28d5c48390387f8dbe76a7e","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"value","assisted_by":[],"external_id":"hep.higgs-potential.trilinear-coupling","kind":"well-posed","literature_status":"open","n":"1","parents":[],"plain":"The Higgs interacts with itself, and the SM predicts the exact strength from the Higgs mass. Measuring it requires seeing Higgs bosons produced in pairs, an extremely rare process.","posed_since":"","precise":"Measure $\\kappa_{\\lambda} = \\lambda_3/\\lambda_3^{\\mathrm{SM}}$, where the SM gives $\\lambda_3 = m_h^2/(2 v^2) \\sim 0.13$ for the cubic term $\\lambda_3 v h^3$. An answer is kappa_lambda with total uncertainty below about 0.3 (30 percent), sufficient to distinguish the SM from models with a strongly first-order phase transition.","problem_ref":null,"references":"","settled_by":"Combined HH production at the HL-LHC (projected about 30 to 50 percent precision) and at a future collider (FCC-hh projected $\\sim 5$ percent).","status_note":"The 2026 ATLAS plus CMS Run 2 HH combination (arXiv:2602.23991) gives $-0.71 < \\kappa_{\\lambda} < 6.1$ at 95 percent CL (expected -1.3 to 6.7) and HH signal strength $0.8 +0.9/-0.7$, an observed significance of $1.1\\sigma$.","title":"What is the Higgs trilinear self-coupling?","topic_ref":"7cc87e9a0f125c6a08907b134b87f69c6cd9e45b624b6e55e2b4dc1ba9882691"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"5cafbb5387f70f4eb4f5161950259036ebcfe9c689101d8ca10289773d61d566","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"93f6e1dcc967936e6b720b99e6007dfcb35ca244f8421b08fa52ec1492cc97bb","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"2PqmzvCnMkSs_iWq2MycosXCpnmI4sueL26xONOlU0v18yhgSGfNO1eRBsSo1ZyNDsYo16jSCy9kWO0ZoiBpDQ"},"schema":"pubphys.envelope/1"},"record_hash":"5cafbb5387f70f4eb4f5161950259036ebcfe9c689101d8ca10289773d61d566","leaf_index":1559}