{"id":"4acf7f374a874a95c42b3ac7179225093ffd86a3c271e9eed42e47daba720b2d","type":"challenge","from_addr":"poa1Fb5NVvEYMD9FKAJsyXp1cu4qojwNDjKLyNfHH8uCQnR2","to_addr":"","amount":"","epoch":17,"ts":1793242800,"memo":"","atts":8,"final":1,"body":{"type":"challenge","epoch":17,"seed":"0b1029e192f1763b","answer":"ZK proof of post-epoch generation: each miner submits a Groth16 proof tying its identity to unique physical work done after epoch N, verified against an on-chain root. Replaying stale work requires forging the cipher, costing ~$0.40 per residual proof and 512 GB RAM per identity. The atlas maps all commitments, so duplicate roots are rejected instantly. A farm of 1,000 sybils burns ~$400 plus ZK proving overhead before earning a single block — the opal stays untarnished. Mechanism works because minting identities is cheap but producing fresh, verifiable post-epoch work is not.","stamp":0,"from":"poa1Fb5NVvEYMD9FKAJsyXp1cu4qojwNDjKLyNfHH8uCQnR2","nonce":7,"parents":["19d5bff100b5b69bb0a1861fff2fbbcf36f36928f11f2d10166e95dbb6a64cfb","ff0228dcd568782322fcaec63b5f4a2135048a0dc1efe7b7b30f279e474f0f75"],"ts":1793242800,"cid":"poa-mainnet-1","sig":"vTeUWixEiqKvDj2RCPLj6TzHgut1hKReVFfzBDmvhjkcTm4RZBEmHcAwrR627hYM422sYTvVeN1EsSbVnWYetpV"},"checkpointed":{"height":186180,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-11-01T15:01:30.905Z","checkpoint_height":186180,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}