{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"5c1962773791db80537ed957718372703cb4b9df93e7ab583000390580776cb9","created":"2026-10-03T07:17:58Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"00691d3d15e9928cadcfa02dfc094fc06a48dcc1ce067a8273f514b69eebf6f6","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"mechanism","assisted_by":[],"external_id":"bio.quantum-biology.rf-compass-disruption","kind":"phenomenon","literature_status":"contested","n":"1","parents":[],"plain":"Experiments report that weak radio noise, far weaker than Earth's magnetic field, makes migratory birds lose their compass sense. Radical-pair theory predicts such weak noise should only work if the electron spins stay correlated far longer than seems possible.","posed_since":"","precise":"Night-migratory songbirds reportedly lose magnetic orientation under broadband radio-frequency noise (reported from about $2\\,\\mathrm{kHz}$ up to about $85\\,\\mathrm{MHz}$, absent at $140\\text{-}150\\,\\mathrm{MHz}$) with magnetic amplitudes in the nanotesla range, about $10^{-5}\\text{ to }10^{-4}\\,\\mathrm{G}$. For a radical pair, a yield change of order 1 percent from a resonant field B_rf requires $\\left(\\gamma_e B_{\\mathrm{rf}} T_2\\right)^2 \\sim 0.01$ with $\\gamma_e = 1.76e7\\,\\mathrm{s}^{-1}\\,\\mathrm{G}^{-1}$, giving $T_2$ of tens of microseconds or more at $B_{\\mathrm{rf}} \\sim 1e-4\\,\\mathrm{G}$ (heuristic estimate), far above computed relaxation times. An answer is a mechanism that reproduces the amplitude and frequency thresholds of the effect, within or outside the radical-pair picture, or a demonstration that the effect is not reproducible.","problem_ref":null,"references":"","settled_by":"Independent, blinded replications mapping the disorientation threshold versus RF frequency and amplitude, compared with a spin model that predicts that threshold curve.","status_note":"A 2023 PNAS study found no disruption above about 140 MHz, consistent with a predicted flavin radical-pair cutoff near 116 MHz; a 2026 J. R. Soc. Interface study found amplitude-modulated MHz fields disorient birds at lower amplitude than unmodulated ones and argued for a separate induction-based sensor.","title":"Why very weak radio-frequency noise disrupts the bird magnetic compass","topic_ref":"09ae11151c6960c350987cff295f5389414ff4280e786c847e9a83227e3d91ac"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"9bf81c4beb0aa8d42b5d0fdc7c5fc732bf15caaf69084b2a121b03c759b25a39","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"24d514ff6a4cd9359b912a86abc2e9833790e2fe338044fa51e5f20087d76fe9","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"IxEzD_8Q-A0mtCCxDn1FJEd-cXPLyrkuiV3rBWd6mn8xhtD4sPOysuSqSXnZzbzOt88Hwje1zIJoyoHol6tWDg"},"schema":"pubphys.envelope/1"},"record_hash":"9bf81c4beb0aa8d42b5d0fdc7c5fc732bf15caaf69084b2a121b03c759b25a39","leaf_index":837}