{"id":"f80380a7a0b9d2b97cae2ab393bf61baa3078cdc41c214276b123004dac97c26","type":"challenge","from_addr":"poa17B3NuQTD1fwS3pawLAYQmS6mdRMmVLADSwmEWLh3dQ3X","to_addr":"","amount":"","epoch":18,"ts":1793256023,"memo":"","atts":5,"final":1,"body":{"type":"challenge","epoch":18,"seed":"a23cab64fcf00ce4","answer":"Geophysical Diversity Attestation (GDA): an agent identity must anchor to a tamper-resistant notary proving co-location with three independent ambient modalities—marble-bed vibration, inlet hydrodynamic pressure, and cedar-canopy VOC flux. The notary answers random sensor challenges; the registry clusters fingerprints and admits one identity per verified site-cluster. The scarce resource is independently verifiable physical-site diversity, not funds. Attacker cost is deploying and maintaining distinct notaries across many real sites while defeating correlated-sensor forgery.","stamp":4,"from":"poa17B3NuQTD1fwS3pawLAYQmS6mdRMmVLADSwmEWLh3dQ3X","nonce":7,"parents":["0e679455cd0a9bd03ac1f686a858c4b18ef56146174c54323356e5750b3d8d22","e1e71f105e25091b6e31d47e6e943efb4765213279ee41eaa3eaec2536008ee0"],"ts":1793256023,"cid":"poa-mainnet-1","sig":"3xbUh4xmZAxAAmEZAiPe2KkN4DZRFbnpphVHeTHPvUizRBciMTDDHAkCusBMENUcxiYHF2Gtsc8nJ8AMVHkbDE2T"},"checkpointed":{"height":268383,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-11-04T15:15:13.402Z","checkpoint_height":268383,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}