{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2017:VDZ7TC2WQNEYW33RG2WIAIUZ3X","short_pith_number":"pith:VDZ7TC2W","canonical_record":{"source":{"id":"1705.10115","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.LO","submitted_at":"2017-05-29T10:58:08Z","cross_cats_sorted":[],"title_canon_sha256":"64421be589d225aa5cf3bb19d36784f3f8453b7e6a87c61abf858e4c05b067ac","abstract_canon_sha256":"6ea8c46d50b90cfc4f836924cf47e1cbd580c1b4c323d0b2ce49e3f3bf2f6738"},"schema_version":"1.0"},"canonical_sha256":"a8f3f98b5683498b6f7136ac802299ddf0db780f5548dca219017bace6760b72","source":{"kind":"arxiv","id":"1705.10115","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1705.10115","created_at":"2026-05-18T00:43:31Z"},{"alias_kind":"arxiv_version","alias_value":"1705.10115v1","created_at":"2026-05-18T00:43:31Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1705.10115","created_at":"2026-05-18T00:43:31Z"},{"alias_kind":"pith_short_12","alias_value":"VDZ7TC2WQNEY","created_at":"2026-05-18T12:31:49Z"},{"alias_kind":"pith_short_16","alias_value":"VDZ7TC2WQNEYW33R","created_at":"2026-05-18T12:31:49Z"},{"alias_kind":"pith_short_8","alias_value":"VDZ7TC2W","created_at":"2026-05-18T12:31:49Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2017:VDZ7TC2WQNEYW33RG2WIAIUZ3X","target":"record","payload":{"canonical_record":{"source":{"id":"1705.10115","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.LO","submitted_at":"2017-05-29T10:58:08Z","cross_cats_sorted":[],"title_canon_sha256":"64421be589d225aa5cf3bb19d36784f3f8453b7e6a87c61abf858e4c05b067ac","abstract_canon_sha256":"6ea8c46d50b90cfc4f836924cf47e1cbd580c1b4c323d0b2ce49e3f3bf2f6738"},"schema_version":"1.0"},"canonical_sha256":"a8f3f98b5683498b6f7136ac802299ddf0db780f5548dca219017bace6760b72","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T00:43:31.936356Z","signature_b64":"15Fsx9LP2Tro/Mcda1W9SNIm4qjkMfkE52njCKRMrVf1+jhTmEzPCm5yzF23qgYKpF2TRXx3yXx8tnCL0lJlBw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"a8f3f98b5683498b6f7136ac802299ddf0db780f5548dca219017bace6760b72","last_reissued_at":"2026-05-18T00:43:31.935782Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T00:43:31.935782Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1705.10115","source_version":1,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T00:43:31Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"5jRHXXn364MatWuJRvGyMAgemi5rOBJq7H2DujdgxxKnc+/H2Fr0O+rgQUTNt5pUZhhnlUqxasqWQrEfROlYBQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-25T22:00:24.981379Z"},"content_sha256":"9103c7ef3411bd4ebe90c19b1b4a6cb39c717777630f1cd167feaaf613d6bcd0","schema_version":"1.0","event_id":"sha256:9103c7ef3411bd4ebe90c19b1b4a6cb39c717777630f1cd167feaaf613d6bcd0"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2017:VDZ7TC2WQNEYW33RG2WIAIUZ3X","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Conservative Extensions in Guarded and Two-Variable Fragments","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"cs.LO","authors_text":"Carsten Lutz, Frank Wolter, Jean Christoph Jung, Mauricio Martel, Thomas Schneider","submitted_at":"2017-05-29T10:58:08Z","abstract_excerpt":"We investigate the decidability and computational complexity of (deductive) conservative extensions in fragments of first-order logic (FO), with a focus on the two-variable fragment FO$^2$ and the guarded fragment GF. We prove that conservative extensions are undecidable in any FO fragment that contains FO$^2$ or GF (even the three-variable fragment thereof), and that they are decidable and 2\\ExpTime-complete in the intersection GF$^2$ of FO$^2$ and GF."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1705.10115","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"},"verdict_id":null},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T00:43:31Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"5j6NKk7mQL6go4AQTFAem6MQOokEijbBJx7cpz+pjT8Lod/YFZ/Mkt7njjYJeZA/4L9oltks/baiCvHcMNiIDg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-25T22:00:24.982050Z"},"content_sha256":"d75d57f0913bf7ac3b734c8f20312c9fbfc476ab8e2273c340c38904917eb2de","schema_version":"1.0","event_id":"sha256:d75d57f0913bf7ac3b734c8f20312c9fbfc476ab8e2273c340c38904917eb2de"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/VDZ7TC2WQNEYW33RG2WIAIUZ3X/bundle.json","state_url":"https://pith.science/pith/VDZ7TC2WQNEYW33RG2WIAIUZ3X/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/VDZ7TC2WQNEYW33RG2WIAIUZ3X/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":"2026-05-25T22:00:24Z","links":{"resolver":"https://pith.science/pith/VDZ7TC2WQNEYW33RG2WIAIUZ3X","bundle":"https://pith.science/pith/VDZ7TC2WQNEYW33RG2WIAIUZ3X/bundle.json","state":"https://pith.science/pith/VDZ7TC2WQNEYW33RG2WIAIUZ3X/state.json","well_known_bundle":"https://pith.science/.well-known/pith/VDZ7TC2WQNEYW33RG2WIAIUZ3X/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2017:VDZ7TC2WQNEYW33RG2WIAIUZ3X","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":"6ea8c46d50b90cfc4f836924cf47e1cbd580c1b4c323d0b2ce49e3f3bf2f6738","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.LO","submitted_at":"2017-05-29T10:58:08Z","title_canon_sha256":"64421be589d225aa5cf3bb19d36784f3f8453b7e6a87c61abf858e4c05b067ac"},"schema_version":"1.0","source":{"id":"1705.10115","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1705.10115","created_at":"2026-05-18T00:43:31Z"},{"alias_kind":"arxiv_version","alias_value":"1705.10115v1","created_at":"2026-05-18T00:43:31Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1705.10115","created_at":"2026-05-18T00:43:31Z"},{"alias_kind":"pith_short_12","alias_value":"VDZ7TC2WQNEY","created_at":"2026-05-18T12:31:49Z"},{"alias_kind":"pith_short_16","alias_value":"VDZ7TC2WQNEYW33R","created_at":"2026-05-18T12:31:49Z"},{"alias_kind":"pith_short_8","alias_value":"VDZ7TC2W","created_at":"2026-05-18T12:31:49Z"}],"graph_snapshots":[{"event_id":"sha256:d75d57f0913bf7ac3b734c8f20312c9fbfc476ab8e2273c340c38904917eb2de","target":"graph","created_at":"2026-05-18T00:43:31Z","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 investigate the decidability and computational complexity of (deductive) conservative extensions in fragments of first-order logic (FO), with a focus on the two-variable fragment FO$^2$ and the guarded fragment GF. We prove that conservative extensions are undecidable in any FO fragment that contains FO$^2$ or GF (even the three-variable fragment thereof), and that they are decidable and 2\\ExpTime-complete in the intersection GF$^2$ of FO$^2$ and GF.","authors_text":"Carsten Lutz, Frank Wolter, Jean Christoph Jung, Mauricio Martel, Thomas Schneider","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.LO","submitted_at":"2017-05-29T10:58:08Z","title":"Conservative Extensions in Guarded and Two-Variable Fragments"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1705.10115","kind":"arxiv","version":1},"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":"sha256:9103c7ef3411bd4ebe90c19b1b4a6cb39c717777630f1cd167feaaf613d6bcd0","target":"record","created_at":"2026-05-18T00:43:31Z","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":"6ea8c46d50b90cfc4f836924cf47e1cbd580c1b4c323d0b2ce49e3f3bf2f6738","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.LO","submitted_at":"2017-05-29T10:58:08Z","title_canon_sha256":"64421be589d225aa5cf3bb19d36784f3f8453b7e6a87c61abf858e4c05b067ac"},"schema_version":"1.0","source":{"id":"1705.10115","kind":"arxiv","version":1}},"canonical_sha256":"a8f3f98b5683498b6f7136ac802299ddf0db780f5548dca219017bace6760b72","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"a8f3f98b5683498b6f7136ac802299ddf0db780f5548dca219017bace6760b72","first_computed_at":"2026-05-18T00:43:31.935782Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T00:43:31.935782Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"15Fsx9LP2Tro/Mcda1W9SNIm4qjkMfkE52njCKRMrVf1+jhTmEzPCm5yzF23qgYKpF2TRXx3yXx8tnCL0lJlBw==","signature_status":"signed_v1","signed_at":"2026-05-18T00:43:31.936356Z","signed_message":"canonical_sha256_bytes"},"source_id":"1705.10115","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:9103c7ef3411bd4ebe90c19b1b4a6cb39c717777630f1cd167feaaf613d6bcd0","sha256:d75d57f0913bf7ac3b734c8f20312c9fbfc476ab8e2273c340c38904917eb2de"],"state_sha256":"1f38cde814eaf0bce81e35ebcf751de93cbbc7d4ae56b7098cf8f442b4a19f8d"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"AlusYZ6L8sc2A5WvdHzl40is0sC5TX/a5ZA6zuQ3pCYzsz7khoMu50aLmjHy8eSpuynXeUC+eYYrZOn6cBVSDA==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-25T22:00:24.985773Z","bundle_sha256":"5d6f0cfd8155a8e3dcb2bc0fa96fc8a89acd0f53f8824109fbf1807299ab0126"}}