{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"75067f38507a850a92778854dac2288f9772b1f4b6ab2b433199f57295ddfcb3","created":"2026-10-15T23:43:22Z","files":[],"origin":{"assisted_by":["ai:gpt-5.5"],"kind":"seed"},"parents":["5cafbb5387f70f4eb4f5161950259036ebcfe9c689101d8ca10289773d61d566","ce59fb6cd812fc05906d0c60a71c75ea22bc686bcf38e7c3ef7010834d98ee7b"],"salt":"9c8f2e7a704f642bb94cbd769abd34be048598d24400236dc0c169a678fff7f0","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"value","assisted_by":["ai:gpt-5.5"],"external_id":"hep.higgs-potential.trilinear-coupling","kind":"well-posed","literature_status":"open","n":"2","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":"5cafbb5387f70f4eb4f5161950259036ebcfe9c689101d8ca10289773d61d566","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":null},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"078d5083c13f2e39348c2f3c68c274474f7a3911a5897c0966460dddcbc94d47","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"d72913e450a3a114d24f4abc76c097432b40debdef02706c8527b382ffc36aff","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"hwNPLqYbPcuhhMA_hUb4kVZecdf1nXGPmcMp6CeACVM8ow3HZn98VZ0jnkBYjrC4W-Czx3Xs_4JI1Rpm7QPTBw"},"schema":"pubphys.envelope/1"},"record_hash":"078d5083c13f2e39348c2f3c68c274474f7a3911a5897c0966460dddcbc94d47","leaf_index":3362}