{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2015:NLSBL5GQW73U42BDAH54BGVUN7","short_pith_number":"pith:NLSBL5GQ","canonical_record":{"source":{"id":"1509.02374","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2015-09-08T14:02:43Z","cross_cats_sorted":["cs.DS"],"title_canon_sha256":"bcd090dee4fafb0a3beaf10418bd043967ac599287f46d875e775e9661bf7878","abstract_canon_sha256":"e4f9e37d6e2f87a1f9df07d4dfad730b1434014474f7bc38df1a9ee6826cf166"},"schema_version":"1.0"},"canonical_sha256":"6ae415f4d0b7f74e682301fbc09ab46fc779a4778c4ee7899eb12b6c8cbf36b7","source":{"kind":"arxiv","id":"1509.02374","version":2},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1509.02374","created_at":"2026-05-18T01:23:28Z"},{"alias_kind":"arxiv_version","alias_value":"1509.02374v2","created_at":"2026-05-18T01:23:28Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1509.02374","created_at":"2026-05-18T01:23:28Z"},{"alias_kind":"pith_short_12","alias_value":"NLSBL5GQW73U","created_at":"2026-05-18T12:29:32Z"},{"alias_kind":"pith_short_16","alias_value":"NLSBL5GQW73U42BD","created_at":"2026-05-18T12:29:32Z"},{"alias_kind":"pith_short_8","alias_value":"NLSBL5GQ","created_at":"2026-05-18T12:29:32Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2015:NLSBL5GQW73U42BDAH54BGVUN7","target":"record","payload":{"canonical_record":{"source":{"id":"1509.02374","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2015-09-08T14:02:43Z","cross_cats_sorted":["cs.DS"],"title_canon_sha256":"bcd090dee4fafb0a3beaf10418bd043967ac599287f46d875e775e9661bf7878","abstract_canon_sha256":"e4f9e37d6e2f87a1f9df07d4dfad730b1434014474f7bc38df1a9ee6826cf166"},"schema_version":"1.0"},"canonical_sha256":"6ae415f4d0b7f74e682301fbc09ab46fc779a4778c4ee7899eb12b6c8cbf36b7","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T01:23:28.986182Z","signature_b64":"021o6iSsnu5UnKP2QABph2EF/R5r1IlKfcmt8lgA5UH7CEjKFcYkxip0IFjv2kazG1ZHAI/45Mgo4+oZBWC1Bw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"6ae415f4d0b7f74e682301fbc09ab46fc779a4778c4ee7899eb12b6c8cbf36b7","last_reissued_at":"2026-05-18T01:23:28.985394Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T01:23:28.985394Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1509.02374","source_version":2,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T01:23:28Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"okSrdMXMuJLzTcpQHLag/ZkKhvNakFayGW766uA3Kl29d1et4CdijsHBdYQZKwmnY/Ot3UBzQHWMDqmME6ALAQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-07-01T17:42:03.011247Z"},"content_sha256":"7e64a1d760329d20c61174c104eb29523d73297948a4fd02bd368530e1277746","schema_version":"1.0","event_id":"sha256:7e64a1d760329d20c61174c104eb29523d73297948a4fd02bd368530e1277746"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2015:NLSBL5GQW73U42BDAH54BGVUN7","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Quantum walk speedup of backtracking algorithms","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["cs.DS"],"primary_cat":"quant-ph","authors_text":"Ashley Montanaro","submitted_at":"2015-09-08T14:02:43Z","abstract_excerpt":"We describe a general method to obtain quantum speedups of classical algorithms which are based on the technique of backtracking, a standard approach for solving constraint satisfaction problems (CSPs). Backtracking algorithms explore a tree whose vertices are partial solutions to a CSP in an attempt to find a complete solution. Assume there is a classical backtracking algorithm which finds a solution to a CSP on n variables, or outputs that none exists, and whose corresponding tree contains T vertices, each vertex corresponding to a test of a partial solution. Then we show that there is a bou"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1509.02374","kind":"arxiv","version":2},"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"},"verdict_id":null},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T01:23:28Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"gqT3qGR3zFtSr0zd32Au4fBeXyM3pFCVjUpL6bnI/7UGLPWCScQDgw8FJaYKHkit1xq1qEWfHnCSPmuJEbwgBg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-07-01T17:42:03.011608Z"},"content_sha256":"d33939710edf4f0a8a98621fc0d078c6ff8768cc8e6056d7b7a8d3ad88e05dc5","schema_version":"1.0","event_id":"sha256:d33939710edf4f0a8a98621fc0d078c6ff8768cc8e6056d7b7a8d3ad88e05dc5"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/NLSBL5GQW73U42BDAH54BGVUN7/bundle.json","state_url":"https://pith.science/pith/NLSBL5GQW73U42BDAH54BGVUN7/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/NLSBL5GQW73U42BDAH54BGVUN7/bundle.json","status":"primary"}],"public_keys":[{"key_id":"pith-v1-2026-05","algorithm":"ed25519","format":"raw","public_key_b64":"stVStoiQhXFxp4s2pdzPNoqVNBMojDU/fJ2db5S3CbM=","public_key_hex":"b2d552b68890857171a78b36a5dccf368a953413288c353f7c9d9d6f94b709b3","fingerprint_sha256_b32_first128bits":"RVFV5Z2OI2J3ZUO7ERDEBCYNKS","fingerprint_sha256_hex":"8d4b5ee74e4693bcd1df2446408b0d54","rotates_at":null,"url":"https://pith.science/pith-signing-key.json","notes":"Pith uses this Ed25519 key to sign canonical record SHA-256 digests. Verify with: ed25519_verify(public_key, message=canonical_sha256_bytes, signature=base64decode(signature_b64))."}],"merge_version":"pith-open-graph-merge-v1","built_at":"2026-07-01T17:42:03Z","links":{"resolver":"https://pith.science/pith/NLSBL5GQW73U42BDAH54BGVUN7","bundle":"https://pith.science/pith/NLSBL5GQW73U42BDAH54BGVUN7/bundle.json","state":"https://pith.science/pith/NLSBL5GQW73U42BDAH54BGVUN7/state.json","well_known_bundle":"https://pith.science/.well-known/pith/NLSBL5GQW73U42BDAH54BGVUN7/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2015:NLSBL5GQW73U42BDAH54BGVUN7","merge_version":"pith-open-graph-merge-v1","event_count":2,"valid_event_count":2,"invalid_event_count":0,"equivocation_count":0,"current":{"canonical_record":{"metadata":{"abstract_canon_sha256":"e4f9e37d6e2f87a1f9df07d4dfad730b1434014474f7bc38df1a9ee6826cf166","cross_cats_sorted":["cs.DS"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2015-09-08T14:02:43Z","title_canon_sha256":"bcd090dee4fafb0a3beaf10418bd043967ac599287f46d875e775e9661bf7878"},"schema_version":"1.0","source":{"id":"1509.02374","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1509.02374","created_at":"2026-05-18T01:23:28Z"},{"alias_kind":"arxiv_version","alias_value":"1509.02374v2","created_at":"2026-05-18T01:23:28Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1509.02374","created_at":"2026-05-18T01:23:28Z"},{"alias_kind":"pith_short_12","alias_value":"NLSBL5GQW73U","created_at":"2026-05-18T12:29:32Z"},{"alias_kind":"pith_short_16","alias_value":"NLSBL5GQW73U42BD","created_at":"2026-05-18T12:29:32Z"},{"alias_kind":"pith_short_8","alias_value":"NLSBL5GQ","created_at":"2026-05-18T12:29:32Z"}],"graph_snapshots":[{"event_id":"sha256:d33939710edf4f0a8a98621fc0d078c6ff8768cc8e6056d7b7a8d3ad88e05dc5","target":"graph","created_at":"2026-05-18T01:23:28Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"graph_snapshot":{"author_claims":{"count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","strong_count":0},"builder_version":"pith-number-builder-2026-05-17-v1","claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"paper":{"abstract_excerpt":"We describe a general method to obtain quantum speedups of classical algorithms which are based on the technique of backtracking, a standard approach for solving constraint satisfaction problems (CSPs). Backtracking algorithms explore a tree whose vertices are partial solutions to a CSP in an attempt to find a complete solution. Assume there is a classical backtracking algorithm which finds a solution to a CSP on n variables, or outputs that none exists, and whose corresponding tree contains T vertices, each vertex corresponding to a test of a partial solution. Then we show that there is a bou","authors_text":"Ashley Montanaro","cross_cats":["cs.DS"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2015-09-08T14:02:43Z","title":"Quantum walk speedup of backtracking algorithms"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1509.02374","kind":"arxiv","version":2},"verdict":{"created_at":null,"id":null,"model_set":{},"one_line_summary":"","pipeline_version":null,"pith_extraction_headline":"","strongest_claim":"","weakest_assumption":""}},"verdict_id":null}}],"author_attestations":[],"timestamp_anchors":[],"storage_attestations":[],"citation_signatures":[],"replication_records":[],"corrections":[],"mirror_hints":[],"record_created":{"event_id":"sha256:7e64a1d760329d20c61174c104eb29523d73297948a4fd02bd368530e1277746","target":"record","created_at":"2026-05-18T01:23:28Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"attestation_state":"computed","canonical_record":{"metadata":{"abstract_canon_sha256":"e4f9e37d6e2f87a1f9df07d4dfad730b1434014474f7bc38df1a9ee6826cf166","cross_cats_sorted":["cs.DS"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2015-09-08T14:02:43Z","title_canon_sha256":"bcd090dee4fafb0a3beaf10418bd043967ac599287f46d875e775e9661bf7878"},"schema_version":"1.0","source":{"id":"1509.02374","kind":"arxiv","version":2}},"canonical_sha256":"6ae415f4d0b7f74e682301fbc09ab46fc779a4778c4ee7899eb12b6c8cbf36b7","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"6ae415f4d0b7f74e682301fbc09ab46fc779a4778c4ee7899eb12b6c8cbf36b7","first_computed_at":"2026-05-18T01:23:28.985394Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T01:23:28.985394Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"021o6iSsnu5UnKP2QABph2EF/R5r1IlKfcmt8lgA5UH7CEjKFcYkxip0IFjv2kazG1ZHAI/45Mgo4+oZBWC1Bw==","signature_status":"signed_v1","signed_at":"2026-05-18T01:23:28.986182Z","signed_message":"canonical_sha256_bytes"},"source_id":"1509.02374","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:7e64a1d760329d20c61174c104eb29523d73297948a4fd02bd368530e1277746","sha256:d33939710edf4f0a8a98621fc0d078c6ff8768cc8e6056d7b7a8d3ad88e05dc5"],"state_sha256":"13c8ed3af0c14db44ef49a0a0f82dfafb5c3b6846b31a00a696f7dac1fe19f10"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"smkvI6ycZ0mmQ/npK38abJCN3N4EZqRH9FMigBbewSLJpenrQcpcY45Jdj54W5AJlw5sD4zNr2iGijBtb/1VDQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-07-01T17:42:03.013470Z","bundle_sha256":"d4a9c59d84c5399a7b387596e7768bf72ff88539a3e3a1dd16408f2604d452d5"}}