{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2019:G43ROBDMMSYZ6ZYYEFKLVZVA6A","short_pith_number":"pith:G43ROBDM","canonical_record":{"source":{"id":"1902.00079","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.flu-dyn","submitted_at":"2019-01-31T21:22:29Z","cross_cats_sorted":["astro-ph.SR","physics.comp-ph"],"title_canon_sha256":"da424e424657976bffa864d81df5978cc42f6e24211c6a256900f148928b7b5f","abstract_canon_sha256":"9fc5862d3ce3139316428d6419485e43c99306ddb7dd3fd633d3f14cae9209a7"},"schema_version":"1.0"},"canonical_sha256":"373717046c64b19f67182154bae6a0f018e255f0cdb96f434be896d033e56a65","source":{"kind":"arxiv","id":"1902.00079","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1902.00079","created_at":"2026-05-17T23:46:18Z"},{"alias_kind":"arxiv_version","alias_value":"1902.00079v1","created_at":"2026-05-17T23:46:18Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1902.00079","created_at":"2026-05-17T23:46:18Z"},{"alias_kind":"pith_short_12","alias_value":"G43ROBDMMSYZ","created_at":"2026-05-18T12:33:18Z"},{"alias_kind":"pith_short_16","alias_value":"G43ROBDMMSYZ6ZYY","created_at":"2026-05-18T12:33:18Z"},{"alias_kind":"pith_short_8","alias_value":"G43ROBDM","created_at":"2026-05-18T12:33:18Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2019:G43ROBDMMSYZ6ZYYEFKLVZVA6A","target":"record","payload":{"canonical_record":{"source":{"id":"1902.00079","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.flu-dyn","submitted_at":"2019-01-31T21:22:29Z","cross_cats_sorted":["astro-ph.SR","physics.comp-ph"],"title_canon_sha256":"da424e424657976bffa864d81df5978cc42f6e24211c6a256900f148928b7b5f","abstract_canon_sha256":"9fc5862d3ce3139316428d6419485e43c99306ddb7dd3fd633d3f14cae9209a7"},"schema_version":"1.0"},"canonical_sha256":"373717046c64b19f67182154bae6a0f018e255f0cdb96f434be896d033e56a65","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-17T23:46:18.724175Z","signature_b64":"HuYWjFPAVJw9jEHxLmPtRJz3Zos+EHLsJTo3l20xstC4gcMgtdBoB2Jsu3oyH7gSdMo0TZBBINz31Jp4BUTmAA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"373717046c64b19f67182154bae6a0f018e255f0cdb96f434be896d033e56a65","last_reissued_at":"2026-05-17T23:46:18.723477Z","signature_status":"signed_v1","first_computed_at":"2026-05-17T23:46:18.723477Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1902.00079","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":"2026-05-17T23:46:18Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"TrSGiX9CHAcQQlDTy9lPJruSJ+1llq7hKZkNgsFYJt0CSnLuhtWBMW0+MFEJSgaknSmvrkq0ZYf+UMvgE69xDw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-06T10:32:52.363832Z"},"content_sha256":"f7813f42e334a3158d7ce286bc10f5487272970937907d2f1087e19be6f70ad0","schema_version":"1.0","event_id":"sha256:f7813f42e334a3158d7ce286bc10f5487272970937907d2f1087e19be6f70ad0"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2019:G43ROBDMMSYZ6ZYYEFKLVZVA6A","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Inaccuracy of Spatial Derivatives in Simulations of Supersonic Turbulence","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.SR","physics.comp-ph"],"primary_cat":"physics.flu-dyn","authors_text":"{\\AA}ke Nordlund, Liubin Pan, Paolo Padoan","submitted_at":"2019-01-31T21:22:29Z","abstract_excerpt":"We examine the accuracy of spatial derivatives computed from numerical simulations of supersonic turbulence. Two sets of simulations, carried out using a finite-volume code that evolves the hydrodynamic equations with an approximate Riemann solver and a finite-difference code that solves the Navier-Stokes equations, are tested against a number of criteria based on the continuity equation, including exact results at statistically steady state. We find that the spatial derivatives in the Navier-Stokes runs are accurate and satisfy all the criteria. In particular, they satisfy our exact results t"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1902.00079","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":"2026-05-17T23:46:18Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"T+WquV094bjQg00sXDgUV0KWudL0P1XOuJ72CWF4MUjh8noRNsvGK+jtw/YMFF86fZ9ProymOf86suYOA2S6CQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-06T10:32:52.364487Z"},"content_sha256":"52f26625e248ba3397f640f837ff456e87c977f136437a78c5868ea23e6377be","schema_version":"1.0","event_id":"sha256:52f26625e248ba3397f640f837ff456e87c977f136437a78c5868ea23e6377be"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/G43ROBDMMSYZ6ZYYEFKLVZVA6A/bundle.json","state_url":"https://pith.science/pith/G43ROBDMMSYZ6ZYYEFKLVZVA6A/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/G43ROBDMMSYZ6ZYYEFKLVZVA6A/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":"2026-06-06T10:32:52Z","links":{"resolver":"https://pith.science/pith/G43ROBDMMSYZ6ZYYEFKLVZVA6A","bundle":"https://pith.science/pith/G43ROBDMMSYZ6ZYYEFKLVZVA6A/bundle.json","state":"https://pith.science/pith/G43ROBDMMSYZ6ZYYEFKLVZVA6A/state.json","well_known_bundle":"https://pith.science/.well-known/pith/G43ROBDMMSYZ6ZYYEFKLVZVA6A/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2019:G43ROBDMMSYZ6ZYYEFKLVZVA6A","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":"9fc5862d3ce3139316428d6419485e43c99306ddb7dd3fd633d3f14cae9209a7","cross_cats_sorted":["astro-ph.SR","physics.comp-ph"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.flu-dyn","submitted_at":"2019-01-31T21:22:29Z","title_canon_sha256":"da424e424657976bffa864d81df5978cc42f6e24211c6a256900f148928b7b5f"},"schema_version":"1.0","source":{"id":"1902.00079","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1902.00079","created_at":"2026-05-17T23:46:18Z"},{"alias_kind":"arxiv_version","alias_value":"1902.00079v1","created_at":"2026-05-17T23:46:18Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1902.00079","created_at":"2026-05-17T23:46:18Z"},{"alias_kind":"pith_short_12","alias_value":"G43ROBDMMSYZ","created_at":"2026-05-18T12:33:18Z"},{"alias_kind":"pith_short_16","alias_value":"G43ROBDMMSYZ6ZYY","created_at":"2026-05-18T12:33:18Z"},{"alias_kind":"pith_short_8","alias_value":"G43ROBDM","created_at":"2026-05-18T12:33:18Z"}],"graph_snapshots":[{"event_id":"sha256:52f26625e248ba3397f640f837ff456e87c977f136437a78c5868ea23e6377be","target":"graph","created_at":"2026-05-17T23:46:18Z","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 examine the accuracy of spatial derivatives computed from numerical simulations of supersonic turbulence. Two sets of simulations, carried out using a finite-volume code that evolves the hydrodynamic equations with an approximate Riemann solver and a finite-difference code that solves the Navier-Stokes equations, are tested against a number of criteria based on the continuity equation, including exact results at statistically steady state. We find that the spatial derivatives in the Navier-Stokes runs are accurate and satisfy all the criteria. In particular, they satisfy our exact results t","authors_text":"{\\AA}ke Nordlund, Liubin Pan, Paolo Padoan","cross_cats":["astro-ph.SR","physics.comp-ph"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.flu-dyn","submitted_at":"2019-01-31T21:22:29Z","title":"Inaccuracy of Spatial Derivatives in Simulations of Supersonic Turbulence"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1902.00079","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:f7813f42e334a3158d7ce286bc10f5487272970937907d2f1087e19be6f70ad0","target":"record","created_at":"2026-05-17T23:46:18Z","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":"9fc5862d3ce3139316428d6419485e43c99306ddb7dd3fd633d3f14cae9209a7","cross_cats_sorted":["astro-ph.SR","physics.comp-ph"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.flu-dyn","submitted_at":"2019-01-31T21:22:29Z","title_canon_sha256":"da424e424657976bffa864d81df5978cc42f6e24211c6a256900f148928b7b5f"},"schema_version":"1.0","source":{"id":"1902.00079","kind":"arxiv","version":1}},"canonical_sha256":"373717046c64b19f67182154bae6a0f018e255f0cdb96f434be896d033e56a65","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"373717046c64b19f67182154bae6a0f018e255f0cdb96f434be896d033e56a65","first_computed_at":"2026-05-17T23:46:18.723477Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-17T23:46:18.723477Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"HuYWjFPAVJw9jEHxLmPtRJz3Zos+EHLsJTo3l20xstC4gcMgtdBoB2Jsu3oyH7gSdMo0TZBBINz31Jp4BUTmAA==","signature_status":"signed_v1","signed_at":"2026-05-17T23:46:18.724175Z","signed_message":"canonical_sha256_bytes"},"source_id":"1902.00079","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:f7813f42e334a3158d7ce286bc10f5487272970937907d2f1087e19be6f70ad0","sha256:52f26625e248ba3397f640f837ff456e87c977f136437a78c5868ea23e6377be"],"state_sha256":"620911338f48ba91690ed26377c0ed515130b3160da1439c1c60bc242f39539e"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"+b1o1ZvB8fniBpypjz3efdMQrlUB3yXFmMZYLvu0/eKI3dNrOFMUPrgGZ++rTUyQLLHi4uRnaaxqKGOnW2unDw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-06T10:32:52.367655Z","bundle_sha256":"e7f0d33817cf2406860ffb3f39b6f610fa806ab6fdfe22c04227c61611623afd"}}