{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2003:ERVUW2IEXRRM3OKYQX6WNWR3R3","short_pith_number":"pith:ERVUW2IE","canonical_record":{"source":{"id":"physics/0305033","kind":"arxiv","version":2},"metadata":{"license":"","primary_cat":"physics.geo-ph","submitted_at":"2003-05-09T10:02:41Z","cross_cats_sorted":["physics.comp-ph"],"title_canon_sha256":"cdfb1dd829aa4cf23e3d790818258bd76c3016f03260df0d6e5f249987104e73","abstract_canon_sha256":"41608d389b9376f06613c223695eeebe9211d9b2466f3d6b1b88243c5a1c14be"},"schema_version":"1.0"},"canonical_sha256":"246b4b6904bc62cdb95885fd66da3b8eccd9e14570365b72b6e830e4d9ef1f63","source":{"kind":"arxiv","id":"physics/0305033","version":2},"source_aliases":[{"alias_kind":"arxiv","alias_value":"physics/0305033","created_at":"2026-05-18T01:38:08Z"},{"alias_kind":"arxiv_version","alias_value":"physics/0305033v2","created_at":"2026-05-18T01:38:08Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.physics/0305033","created_at":"2026-05-18T01:38:08Z"},{"alias_kind":"pith_short_12","alias_value":"ERVUW2IEXRRM","created_at":"2026-05-18T12:25:51Z"},{"alias_kind":"pith_short_16","alias_value":"ERVUW2IEXRRM3OKY","created_at":"2026-05-18T12:25:51Z"},{"alias_kind":"pith_short_8","alias_value":"ERVUW2IE","created_at":"2026-05-18T12:25:51Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2003:ERVUW2IEXRRM3OKYQX6WNWR3R3","target":"record","payload":{"canonical_record":{"source":{"id":"physics/0305033","kind":"arxiv","version":2},"metadata":{"license":"","primary_cat":"physics.geo-ph","submitted_at":"2003-05-09T10:02:41Z","cross_cats_sorted":["physics.comp-ph"],"title_canon_sha256":"cdfb1dd829aa4cf23e3d790818258bd76c3016f03260df0d6e5f249987104e73","abstract_canon_sha256":"41608d389b9376f06613c223695eeebe9211d9b2466f3d6b1b88243c5a1c14be"},"schema_version":"1.0"},"canonical_sha256":"246b4b6904bc62cdb95885fd66da3b8eccd9e14570365b72b6e830e4d9ef1f63","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T01:38:08.902418Z","signature_b64":"ZLn32CWX0ck/AGrYOzwx1LQiUB6C4cEAeHFZCdEsKeL6u07Ea6AvR5FEEHNQyIBr6Va/4Rh4oDl7SFUHjlgSDQ==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"246b4b6904bc62cdb95885fd66da3b8eccd9e14570365b72b6e830e4d9ef1f63","last_reissued_at":"2026-05-18T01:38:08.901873Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T01:38:08.901873Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"physics/0305033","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":"2026-05-18T01:38:08Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"YzPMJ3bIh8f8WNYGzzG/MEMhmGawJ2+RqJAkxlEcqN4V4z6Z+ZOKWLLqJn8fqitcPy1TvAqzeAaTsRzRCPozDQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-31T04:19:35.591672Z"},"content_sha256":"1e050fdfa9ad6dd9fe732c2e9297f955058121bd483848c53c80e5c42fa3ce30","schema_version":"1.0","event_id":"sha256:1e050fdfa9ad6dd9fe732c2e9297f955058121bd483848c53c80e5c42fa3ce30"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2003:ERVUW2IEXRRM3OKYQX6WNWR3R3","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"The particle-in-cell model for ab initio thermodynamics: implications for the elastic anisotropy of the Earth's inner core","license":"","headline":"","cross_cats":["physics.comp-ph"],"primary_cat":"physics.geo-ph","authors_text":"2), (2) Research School of Geological, Astronomy Department, Birkbeck, C. M. S. Gannarelli (1), D. Alfe (1, Geophysical Sciences, M. J. Gillan (1) ((1) Physics, University College London, University College London)","submitted_at":"2003-05-09T10:02:41Z","abstract_excerpt":"We assess the quantitative accuracy of the particle-in-cell (PIC) approximation used in recent ab initio predictions of the thermodynamic properties of hexagonal-close-packed iron at the conditions of the Earth's inner core. The assessment is made by comparing PIC predictions for a range of thermodynamic properties with the results of more exact calculations that avoid the PIC approximation. It is shown that PIC gives very accurate results for some properties, but that it gives an incorrect treatment of anharmonic lattice vibrations. In addition, our assessment does not support recent PIC-base"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"physics/0305033","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":"2026-05-18T01:38:08Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"6A+0GefTEn55fM+XpPw0hi0Rm658mFRS9zh3LfqvdgH29R5+/nrkbdO831pyWZaxk8bTZBJ62bqx7j6IKzrqAg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-31T04:19:35.592400Z"},"content_sha256":"71de207d91497e320f5ab37c512064f4b7a1ea4c44cef36bdb449455def35c62","schema_version":"1.0","event_id":"sha256:71de207d91497e320f5ab37c512064f4b7a1ea4c44cef36bdb449455def35c62"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/ERVUW2IEXRRM3OKYQX6WNWR3R3/bundle.json","state_url":"https://pith.science/pith/ERVUW2IEXRRM3OKYQX6WNWR3R3/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/ERVUW2IEXRRM3OKYQX6WNWR3R3/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":"2026-05-31T04:19:35Z","links":{"resolver":"https://pith.science/pith/ERVUW2IEXRRM3OKYQX6WNWR3R3","bundle":"https://pith.science/pith/ERVUW2IEXRRM3OKYQX6WNWR3R3/bundle.json","state":"https://pith.science/pith/ERVUW2IEXRRM3OKYQX6WNWR3R3/state.json","well_known_bundle":"https://pith.science/.well-known/pith/ERVUW2IEXRRM3OKYQX6WNWR3R3/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2003:ERVUW2IEXRRM3OKYQX6WNWR3R3","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":"41608d389b9376f06613c223695eeebe9211d9b2466f3d6b1b88243c5a1c14be","cross_cats_sorted":["physics.comp-ph"],"license":"","primary_cat":"physics.geo-ph","submitted_at":"2003-05-09T10:02:41Z","title_canon_sha256":"cdfb1dd829aa4cf23e3d790818258bd76c3016f03260df0d6e5f249987104e73"},"schema_version":"1.0","source":{"id":"physics/0305033","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"physics/0305033","created_at":"2026-05-18T01:38:08Z"},{"alias_kind":"arxiv_version","alias_value":"physics/0305033v2","created_at":"2026-05-18T01:38:08Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.physics/0305033","created_at":"2026-05-18T01:38:08Z"},{"alias_kind":"pith_short_12","alias_value":"ERVUW2IEXRRM","created_at":"2026-05-18T12:25:51Z"},{"alias_kind":"pith_short_16","alias_value":"ERVUW2IEXRRM3OKY","created_at":"2026-05-18T12:25:51Z"},{"alias_kind":"pith_short_8","alias_value":"ERVUW2IE","created_at":"2026-05-18T12:25:51Z"}],"graph_snapshots":[{"event_id":"sha256:71de207d91497e320f5ab37c512064f4b7a1ea4c44cef36bdb449455def35c62","target":"graph","created_at":"2026-05-18T01:38:08Z","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 assess the quantitative accuracy of the particle-in-cell (PIC) approximation used in recent ab initio predictions of the thermodynamic properties of hexagonal-close-packed iron at the conditions of the Earth's inner core. The assessment is made by comparing PIC predictions for a range of thermodynamic properties with the results of more exact calculations that avoid the PIC approximation. It is shown that PIC gives very accurate results for some properties, but that it gives an incorrect treatment of anharmonic lattice vibrations. In addition, our assessment does not support recent PIC-base","authors_text":"2), (2) Research School of Geological, Astronomy Department, Birkbeck, C. M. S. Gannarelli (1), D. Alfe (1, Geophysical Sciences, M. J. Gillan (1) ((1) Physics, University College London, University College London)","cross_cats":["physics.comp-ph"],"headline":"","license":"","primary_cat":"physics.geo-ph","submitted_at":"2003-05-09T10:02:41Z","title":"The particle-in-cell model for ab initio thermodynamics: implications for the elastic anisotropy of the Earth's inner core"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"physics/0305033","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":"sha256:1e050fdfa9ad6dd9fe732c2e9297f955058121bd483848c53c80e5c42fa3ce30","target":"record","created_at":"2026-05-18T01:38:08Z","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":"41608d389b9376f06613c223695eeebe9211d9b2466f3d6b1b88243c5a1c14be","cross_cats_sorted":["physics.comp-ph"],"license":"","primary_cat":"physics.geo-ph","submitted_at":"2003-05-09T10:02:41Z","title_canon_sha256":"cdfb1dd829aa4cf23e3d790818258bd76c3016f03260df0d6e5f249987104e73"},"schema_version":"1.0","source":{"id":"physics/0305033","kind":"arxiv","version":2}},"canonical_sha256":"246b4b6904bc62cdb95885fd66da3b8eccd9e14570365b72b6e830e4d9ef1f63","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"246b4b6904bc62cdb95885fd66da3b8eccd9e14570365b72b6e830e4d9ef1f63","first_computed_at":"2026-05-18T01:38:08.901873Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T01:38:08.901873Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"ZLn32CWX0ck/AGrYOzwx1LQiUB6C4cEAeHFZCdEsKeL6u07Ea6AvR5FEEHNQyIBr6Va/4Rh4oDl7SFUHjlgSDQ==","signature_status":"signed_v1","signed_at":"2026-05-18T01:38:08.902418Z","signed_message":"canonical_sha256_bytes"},"source_id":"physics/0305033","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:1e050fdfa9ad6dd9fe732c2e9297f955058121bd483848c53c80e5c42fa3ce30","sha256:71de207d91497e320f5ab37c512064f4b7a1ea4c44cef36bdb449455def35c62"],"state_sha256":"fb4e743bd63ddac3dcae3838435430545e36c72518800a6cb8e55bf56df9d42a"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"wi60u7Wdh4lRLcGTXaWmIzO+ixesugFhKcFKAC+Kg3FtyyCbsY7lbZNVE/LIELiaPnJmdNFVCc2SBamz7qixAg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-31T04:19:35.596300Z","bundle_sha256":"e612468d0a8cfcf843ee11f82dd73c4d54da33816522eb1eec3b9bdda2550ad2"}}