{"record_type":"pith_number_record","schema_url":"https://pith.science/schemas/pith-number/v1.json","pith_number":"pith:2015:UVPEM76OB7I6W32A2276GJU2IW","short_pith_number":"pith:UVPEM76O","schema_version":"1.0","canonical_sha256":"a55e467fce0fd1eb6f40d6bfe3269a459554a3c69fe8aebb3a7926c9bfc014de","source":{"kind":"arxiv","id":"1504.07621","version":1},"attestation_state":"computed","paper":{"title":"Condensed Unpredictability","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"cs.CR","authors_text":"Alexander Golovnev, Krzysztof Pietrzak, Maciej Skorski","submitted_at":"2015-04-28T19:59:54Z","abstract_excerpt":"We consider the task of deriving a key with high HILL entropy from an unpredictable source. Previous to this work, the only known way to transform unpredictability into a key that was $\\eps$ indistinguishable from having min-entropy was via pseudorandomness, for example by Goldreich-Levin (GL) hardcore bits. This approach has the inherent limitation that from a source with $k$ bits of unpredictability entropy one can derive a key of length (and thus HILL entropy) at most $k-2\\log(1/\\epsilon)$ bits. In many settings, e.g. when dealing with biometric data, such a $2\\log(1/\\epsilon)$ bit entropy "},"verification_status":{"content_addressed":true,"pith_receipt":true,"author_attested":false,"weak_author_claims":0,"strong_author_claims":0,"externally_anchored":false,"storage_verified":false,"citation_signatures":0,"replication_records":0,"graph_snapshot":true,"references_resolved":false,"formal_links_present":false},"canonical_record":{"source":{"id":"1504.07621","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.CR","submitted_at":"2015-04-28T19:59:54Z","cross_cats_sorted":[],"title_canon_sha256":"c48f93266393aff3a365823eb2ad16bc8e59309763f9b124191fdcc178bb1401","abstract_canon_sha256":"fa4659bf2c657c07f3d6bcbe6cac44d96c48c11e4bb3ca3327400109021132bd"},"schema_version":"1.0"},"receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T02:17:34.187351Z","signature_b64":"6IU0GVO9dWSVW3YGexo0dCJNJbE5l3Fp1NvBf3x1N59HfbMO+uh7sv2qdjlGJsfkHo9GrBJwDwbnirLycOVsBQ==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"a55e467fce0fd1eb6f40d6bfe3269a459554a3c69fe8aebb3a7926c9bfc014de","last_reissued_at":"2026-05-18T02:17:34.186643Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T02:17:34.186643Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"graph_snapshot":{"paper":{"title":"Condensed Unpredictability","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"cs.CR","authors_text":"Alexander Golovnev, Krzysztof Pietrzak, Maciej Skorski","submitted_at":"2015-04-28T19:59:54Z","abstract_excerpt":"We consider the task of deriving a key with high HILL entropy from an unpredictable source. Previous to this work, the only known way to transform unpredictability into a key that was $\\eps$ indistinguishable from having min-entropy was via pseudorandomness, for example by Goldreich-Levin (GL) hardcore bits. This approach has the inherent limitation that from a source with $k$ bits of unpredictability entropy one can derive a key of length (and thus HILL entropy) at most $k-2\\log(1/\\epsilon)$ bits. In many settings, e.g. when dealing with biometric data, such a $2\\log(1/\\epsilon)$ bit entropy "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1504.07621","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"},"aliases":[{"alias_kind":"arxiv","alias_value":"1504.07621","created_at":"2026-05-18T02:17:34.186755+00:00"},{"alias_kind":"arxiv_version","alias_value":"1504.07621v1","created_at":"2026-05-18T02:17:34.186755+00:00"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1504.07621","created_at":"2026-05-18T02:17:34.186755+00:00"},{"alias_kind":"pith_short_12","alias_value":"UVPEM76OB7I6","created_at":"2026-05-18T12:29:44.643036+00:00"},{"alias_kind":"pith_short_16","alias_value":"UVPEM76OB7I6W32A","created_at":"2026-05-18T12:29:44.643036+00:00"},{"alias_kind":"pith_short_8","alias_value":"UVPEM76O","created_at":"2026-05-18T12:29:44.643036+00:00"}],"events":[],"event_summary":{},"paper_claims":[],"inbound_citations":{"count":0,"internal_anchor_count":0,"sample":[]},"formal_canon":{"evidence_count":0,"sample":[],"anchors":[]},"links":{"html":"https://pith.science/pith/UVPEM76OB7I6W32A2276GJU2IW","json":"https://pith.science/pith/UVPEM76OB7I6W32A2276GJU2IW.json","graph_json":"https://pith.science/api/pith-number/UVPEM76OB7I6W32A2276GJU2IW/graph.json","events_json":"https://pith.science/api/pith-number/UVPEM76OB7I6W32A2276GJU2IW/events.json","paper":"https://pith.science/paper/UVPEM76O"},"agent_actions":{"view_html":"https://pith.science/pith/UVPEM76OB7I6W32A2276GJU2IW","download_json":"https://pith.science/pith/UVPEM76OB7I6W32A2276GJU2IW.json","view_paper":"https://pith.science/paper/UVPEM76O","resolve_alias":"https://pith.science/api/pith-number/resolve?arxiv=1504.07621&json=true","fetch_graph":"https://pith.science/api/pith-number/UVPEM76OB7I6W32A2276GJU2IW/graph.json","fetch_events":"https://pith.science/api/pith-number/UVPEM76OB7I6W32A2276GJU2IW/events.json","actions":{"anchor_timestamp":"https://pith.science/pith/UVPEM76OB7I6W32A2276GJU2IW/action/timestamp_anchor","attest_storage":"https://pith.science/pith/UVPEM76OB7I6W32A2276GJU2IW/action/storage_attestation","attest_author":"https://pith.science/pith/UVPEM76OB7I6W32A2276GJU2IW/action/author_attestation","sign_citation":"https://pith.science/pith/UVPEM76OB7I6W32A2276GJU2IW/action/citation_signature","submit_replication":"https://pith.science/pith/UVPEM76OB7I6W32A2276GJU2IW/action/replication_record"}},"created_at":"2026-05-18T02:17:34.186755+00:00","updated_at":"2026-05-18T02:17:34.186755+00:00"}