{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"bfb73313e80297d7c03b3778eaf84397acb02696ed11add38a3467d3b994c2d2","created":"2026-10-15T23:43:22Z","files":[],"origin":{"assisted_by":["ai:gpt-5.5"],"kind":"seed"},"parents":["27a7eedba88ca215a2009212dc8c084ebb020e149079d310d3b01a41501b4f43","ce59fb6cd812fc05906d0c60a71c75ea22bc686bcf38e7c3ef7010834d98ee7b"],"salt":"789bc537108e7d2e22b831e378eda6f0182d05b46641fcb8dafbf411679664cb","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"yes-no","assisted_by":["ai:gpt-5.5"],"external_id":"cm.hydrides.magnetic-evidence","kind":"well-posed","literature_status":"partially-resolved","n":"2","parents":[],"plain":"Hydride samples are tiny and are enclosed in diamond cells, so measuring the magnetic field expulsion that defines a superconductor is hard, and some published magnetic data have been challenged.","posed_since":"2015","precise":"For $\\mathrm{H_3S}$ and $\\mathrm{LaH_{10}}$ at $\\sim 1.5 \\text{ to } 1.9 \\mathrm{Mbar}$, establish bulk magnetic signatures (flux expulsion, trapped flux, penetration depth $\\lambda_L$, critical current) that agree quantitatively with the resistive transitions and with the Ginzburg-Landau parameters implied by $H_c2$. An answer is a magnetic measurement reproduced by independent groups with consistent volume fraction and $\\lambda_L$.","problem_ref":"27a7eedba88ca215a2009212dc8c084ebb020e149079d310d3b01a41501b4f43","references":"","settled_by":"Independent replication of magnetization or local magnetometry on $\\mathrm{H_3S}$ or $\\mathrm{LaH_{10}}$ with quantitative agreement among volume fraction, $\\lambda_L$ and $H_c2$.","status_note":"Nitrogen-vacancy magnetometry imaging of flux expulsion in a cerium hydride (2024) and tunneling measurement of a gap near $60\\,\\mathrm{meV}$ in $\\mathrm{H_3S}$ (2025) support superconductivity; some magnetization data sets remain disputed.","title":"Do megabar hydrides show consistent bulk magnetic evidence of superconductivity?","topic_ref":null},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"ca639a9923bb4ec2a7f697a98abeb7acaaf4a3a93d270b0a79029e96e78923be","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"e853590386b8f5f200d36cece75226c7f6603d8261b1d5deadae4536826aff4e","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"39ZgSnazuC78BakuVoHH1xBb4ZSrxRy7hKKzrxByyjRR1gU-UtPBtCagAP0SHorYe8W-HbDh89_32tqNK3jhBw"},"schema":"pubphys.envelope/1"},"record_hash":"ca639a9923bb4ec2a7f697a98abeb7acaaf4a3a93d270b0a79029e96e78923be","leaf_index":2862}