{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"8fd0f6400779edb49b5420652dec5fb651d8608b0588dbfdad7f4dd34ec0189d","created":"2026-10-03T07:18:03Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"45fe86da3a2fee05faa86af1ca0e82e5a9c3e8ac38495e028fd20c8890bb41e5","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"value","assisted_by":[],"external_id":"earth.inner-core.core-conductivity","kind":"well-posed","literature_status":"contested","n":"1","parents":[],"plain":"How well molten iron conducts heat under core pressures controls how much heat is left to stir the core. Calculations and lab experiments disagree by a large factor.","posed_since":"","precise":"Determine the thermal conductivity $k$ of the outer-core Fe-Ni-light-element liquid at $P \\sim 1.36e12\\,\\mathrm{dyn}/\\mathrm{cm}^2$ and $T \\sim 4000\\,\\mathrm{K}$. Ab initio calculations give $k$ of order $1e7\\ \\text{to}\\ 2.5e7\\,\\mathrm{erg}/(\\mathrm{s}\\,\\mathrm{cm}\\,\\mathrm{K})$ while some laser-heated diamond-anvil measurements give values near $3e6\\,\\mathrm{erg}/(\\mathrm{s}\\,\\mathrm{cm}\\,\\mathrm{K})$. An answer is $k$ with about 20 percent uncertainty including light-element and electron-electron scattering contributions.","problem_ref":null,"references":"","settled_by":"Concordant dynamic or static high-pressure transport measurements at core conditions and ab initio calculations including electron-electron scattering.","status_note":"Experiment-theory disagreement persists as of 2024 to 2025, with new calculations for Fe-H and Fe-Si alloys (e.g. arXiv:2408.04521).","title":"Thermal conductivity of liquid iron alloy at core-mantle boundary conditions","topic_ref":"7cfe9fc58e1f6e93abcae219320fa93156a5400d6286e67a83bb0bb8981c5f56"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"1fc9f206aed3d35a921169e38cb284d232b5b0356f375c9a4e47fe835aef0623","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"c636bca2225825bda46989d0d28dda22e4107b5156dfe8a074d5b0f80708cc4a","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"70-nPLhq1Rp4-pY1cmmne1n7ZF09k15ePgmoYLwafmikn2AlSCPBnfm0XHorAheo-pw0m50APPi4pybBFSVdBw"},"schema":"pubphys.envelope/1"},"record_hash":"1fc9f206aed3d35a921169e38cb284d232b5b0356f375c9a4e47fe835aef0623","leaf_index":1330}