{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2019:FVZ3AYXJBMP5XFO5MPE2NXEMZO","short_pith_number":"pith:FVZ3AYXJ","canonical_record":{"source":{"id":"1906.04211","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.stat-mech","submitted_at":"2019-06-10T18:13:09Z","cross_cats_sorted":["cond-mat.str-el","hep-th","quant-ph"],"title_canon_sha256":"6ae53095b9cec95d75f929c1fa03b4cb9be49cb0b6b6c57e3366e72c9dd3a207","abstract_canon_sha256":"057a812c0f1de927d3f2843f42ed15f1a3a86c9e09d6eb008e4da24603a0eb43"},"schema_version":"1.0"},"canonical_sha256":"2d73b062e90b1fdb95dd63c9a6dc8ccb9a35e7acdefe0b339b514924b22f4198","source":{"kind":"arxiv","id":"1906.04211","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1906.04211","created_at":"2026-07-05T00:06:46Z"},{"alias_kind":"arxiv_version","alias_value":"1906.04211v1","created_at":"2026-07-05T00:06:46Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1906.04211","created_at":"2026-07-05T00:06:46Z"},{"alias_kind":"pith_short_12","alias_value":"FVZ3AYXJBMP5","created_at":"2026-07-05T00:06:46Z"},{"alias_kind":"pith_short_16","alias_value":"FVZ3AYXJBMP5XFO5","created_at":"2026-07-05T00:06:46Z"},{"alias_kind":"pith_short_8","alias_value":"FVZ3AYXJ","created_at":"2026-07-05T00:06:46Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2019:FVZ3AYXJBMP5XFO5MPE2NXEMZO","target":"record","payload":{"canonical_record":{"source":{"id":"1906.04211","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.stat-mech","submitted_at":"2019-06-10T18:13:09Z","cross_cats_sorted":["cond-mat.str-el","hep-th","quant-ph"],"title_canon_sha256":"6ae53095b9cec95d75f929c1fa03b4cb9be49cb0b6b6c57e3366e72c9dd3a207","abstract_canon_sha256":"057a812c0f1de927d3f2843f42ed15f1a3a86c9e09d6eb008e4da24603a0eb43"},"schema_version":"1.0"},"canonical_sha256":"2d73b062e90b1fdb95dd63c9a6dc8ccb9a35e7acdefe0b339b514924b22f4198","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-05T00:06:46.017798Z","signature_b64":"LH1wvte9pSNYyoWfuaQklbqCXMsf5xH7SdS/mZh1RS17YHUsuG06GnH/8hJJVmQVpCmT9OdvUwo0yjOGEtcmCQ==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"2d73b062e90b1fdb95dd63c9a6dc8ccb9a35e7acdefe0b339b514924b22f4198","last_reissued_at":"2026-07-05T00:06:46.017410Z","signature_status":"signed_v1","first_computed_at":"2026-07-05T00:06:46.017410Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1906.04211","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":"2026-07-05T00:06:46Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"uPxKLvRMGvJ0UDG5MZiPG+3QutiRRboMHMRFLjY17KW7jtQagIORhruiWM60iF0MuGINp+1zn044pcUtx3TNDw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-09T06:05:36.580107Z"},"content_sha256":"752ede32f1d6cd5082fc286cbede7ea4d64a15b3b6a544ff384f215d521e63d4","schema_version":"1.0","event_id":"sha256:752ede32f1d6cd5082fc286cbede7ea4d64a15b3b6a544ff384f215d521e63d4"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2019:FVZ3AYXJBMP5XFO5MPE2NXEMZO","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Twisted and untwisted negativity spectrum of free fermions","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["cond-mat.str-el","hep-th","quant-ph"],"primary_cat":"cond-mat.stat-mech","authors_text":"Hassan Shapourian, Paola Ruggiero, Pasquale Calabrese, Shinsei Ryu","submitted_at":"2019-06-10T18:13:09Z","abstract_excerpt":"A basic diagnostic of entanglement in mixed quantum states is known as the positive partial transpose (PT) criterion. Such criterion is based on the observation that the spectrum of the partially transposed density matrix of an entangled state contains negative eigenvalues, in turn, used to define an entanglement measure called the logarithmic negativity. Despite the great success of logarithmic negativity in characterizing bosonic many-body systems, generalizing the operation of PT to fermionic systems remained a technical challenge until recently when a more natural definition of PT for ferm"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1906.04211","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":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/1906.04211/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"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":"2026-07-05T00:06:46Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"FPiMaKrAwBrUfuXD5fHwrQu7rlUHlDb35T4oOmRzp2gKmVevtRU3hk/LSFEIRTd2VWosLngqWg0tP7JDAxp+Dw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-09T06:05:36.581076Z"},"content_sha256":"a78f9cf367856a371be3f5501536cedfccbd9e3ed12444bbe94ec9df102438d1","schema_version":"1.0","event_id":"sha256:a78f9cf367856a371be3f5501536cedfccbd9e3ed12444bbe94ec9df102438d1"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/FVZ3AYXJBMP5XFO5MPE2NXEMZO/bundle.json","state_url":"https://pith.science/pith/FVZ3AYXJBMP5XFO5MPE2NXEMZO/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/FVZ3AYXJBMP5XFO5MPE2NXEMZO/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":"2026-08-09T06:05:36Z","links":{"resolver":"https://pith.science/pith/FVZ3AYXJBMP5XFO5MPE2NXEMZO","bundle":"https://pith.science/pith/FVZ3AYXJBMP5XFO5MPE2NXEMZO/bundle.json","state":"https://pith.science/pith/FVZ3AYXJBMP5XFO5MPE2NXEMZO/state.json","well_known_bundle":"https://pith.science/.well-known/pith/FVZ3AYXJBMP5XFO5MPE2NXEMZO/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2019:FVZ3AYXJBMP5XFO5MPE2NXEMZO","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":"057a812c0f1de927d3f2843f42ed15f1a3a86c9e09d6eb008e4da24603a0eb43","cross_cats_sorted":["cond-mat.str-el","hep-th","quant-ph"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.stat-mech","submitted_at":"2019-06-10T18:13:09Z","title_canon_sha256":"6ae53095b9cec95d75f929c1fa03b4cb9be49cb0b6b6c57e3366e72c9dd3a207"},"schema_version":"1.0","source":{"id":"1906.04211","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1906.04211","created_at":"2026-07-05T00:06:46Z"},{"alias_kind":"arxiv_version","alias_value":"1906.04211v1","created_at":"2026-07-05T00:06:46Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1906.04211","created_at":"2026-07-05T00:06:46Z"},{"alias_kind":"pith_short_12","alias_value":"FVZ3AYXJBMP5","created_at":"2026-07-05T00:06:46Z"},{"alias_kind":"pith_short_16","alias_value":"FVZ3AYXJBMP5XFO5","created_at":"2026-07-05T00:06:46Z"},{"alias_kind":"pith_short_8","alias_value":"FVZ3AYXJ","created_at":"2026-07-05T00:06:46Z"}],"graph_snapshots":[{"event_id":"sha256:a78f9cf367856a371be3f5501536cedfccbd9e3ed12444bbe94ec9df102438d1","target":"graph","created_at":"2026-07-05T00:06:46Z","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"},"integrity":{"available":true,"clean":true,"detectors_run":[],"endpoint":"/pith/1906.04211/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"A basic diagnostic of entanglement in mixed quantum states is known as the positive partial transpose (PT) criterion. Such criterion is based on the observation that the spectrum of the partially transposed density matrix of an entangled state contains negative eigenvalues, in turn, used to define an entanglement measure called the logarithmic negativity. Despite the great success of logarithmic negativity in characterizing bosonic many-body systems, generalizing the operation of PT to fermionic systems remained a technical challenge until recently when a more natural definition of PT for ferm","authors_text":"Hassan Shapourian, Paola Ruggiero, Pasquale Calabrese, Shinsei Ryu","cross_cats":["cond-mat.str-el","hep-th","quant-ph"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.stat-mech","submitted_at":"2019-06-10T18:13:09Z","title":"Twisted and untwisted negativity spectrum of free fermions"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1906.04211","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":"sha256:752ede32f1d6cd5082fc286cbede7ea4d64a15b3b6a544ff384f215d521e63d4","target":"record","created_at":"2026-07-05T00:06:46Z","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":"057a812c0f1de927d3f2843f42ed15f1a3a86c9e09d6eb008e4da24603a0eb43","cross_cats_sorted":["cond-mat.str-el","hep-th","quant-ph"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.stat-mech","submitted_at":"2019-06-10T18:13:09Z","title_canon_sha256":"6ae53095b9cec95d75f929c1fa03b4cb9be49cb0b6b6c57e3366e72c9dd3a207"},"schema_version":"1.0","source":{"id":"1906.04211","kind":"arxiv","version":1}},"canonical_sha256":"2d73b062e90b1fdb95dd63c9a6dc8ccb9a35e7acdefe0b339b514924b22f4198","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"2d73b062e90b1fdb95dd63c9a6dc8ccb9a35e7acdefe0b339b514924b22f4198","first_computed_at":"2026-07-05T00:06:46.017410Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T00:06:46.017410Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"LH1wvte9pSNYyoWfuaQklbqCXMsf5xH7SdS/mZh1RS17YHUsuG06GnH/8hJJVmQVpCmT9OdvUwo0yjOGEtcmCQ==","signature_status":"signed_v1","signed_at":"2026-07-05T00:06:46.017798Z","signed_message":"canonical_sha256_bytes"},"source_id":"1906.04211","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:752ede32f1d6cd5082fc286cbede7ea4d64a15b3b6a544ff384f215d521e63d4","sha256:a78f9cf367856a371be3f5501536cedfccbd9e3ed12444bbe94ec9df102438d1"],"state_sha256":"20a3e11508fff56466d09715d68c7785bc28dfb3b995da70dafec0d83f5a5638"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"vEFGb2tkJnKrONTTOqr+if1mDoLUvzZvubgW/+GAAMpZ5TFHpaFeiGfk/cR/WGpNbJ2zsEJrlGY9eHtfi3/4Dg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-08-09T06:05:36.588197Z","bundle_sha256":"8fc1fdd9733f996f1559baf7a9c2976a98c6690349b709adb74fe6c3e2d8e2c4"}}