{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"1b9ffdc5c734204bda0b95d5ee55133c3a81b285a6c4389eb741cfcfafbd15c4","created":"2026-10-03T07:18:02Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"28827c0cc12a0c09075439104e327a67580f49c08a82be0b49c62b556629c016","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"identification","assisted_by":[],"external_id":"cosmo.cosmic-magnetism.seed-origin","kind":"phenomenon","literature_status":"open","n":"1","parents":[],"plain":"Dynamos in galaxies can amplify a weak magnetic field, but they need a starting seed. The seed could come from the early universe or from the first stars and galaxies.","posed_since":"","precise":"Galaxies and clusters host fields of ~1e-6 G coherent over $\\sim 10\\,\\mathrm{kpc}$, amplified by dynamos from seeds $B_{\\mathrm{seed}}$. Identify the origin of the seeds: Biermann battery in the first collapsed structures (~1e-20 G), inflationary magnetogenesis, or first-order phase transitions. An answer identifies the origin through the void field strength, coherence length and helicity, which differ between scenarios.","problem_ref":null,"references":"","settled_by":"Measured strength, coherence length and helicity of void fields compared with the predictions of each scenario.","status_note":"","title":"Were cosmic magnetic seed fields primordial or astrophysical?","topic_ref":"4a10d151d11d41a3a49cfa9ae855770ef191bf64efebccf6b46e1162c895e62e"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"758593ddd21934f5cafd29de60d162dd327db8579db4b33708c8bb9394fd068a","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"576534340b2815e18f7b3889bb67876d101a4b9ab036b2033bf76c208189c48f","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"Pv7N21THvkIsHvzB1fQPcv0HWc78p75mB-lqdtUxCMrXSSLaigam4LX1lLiiEFn7E9BcOkiisVLyJnsiYpyIDQ"},"schema":"pubphys.envelope/1"},"record_hash":"758593ddd21934f5cafd29de60d162dd327db8579db4b33708c8bb9394fd068a","leaf_index":1235}