{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2018:7ZCIFFHWN4436DTTK3FQ4TI5KO","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":"a713e71462407a8ae35d30bc8b89a4dfe65dd8034b62959ded266e50eee85106","cross_cats_sorted":["physics.ao-ph"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.flu-dyn","submitted_at":"2018-11-20T14:17:48Z","title_canon_sha256":"cef0b265bcedc739b532d41646fbf4b09c35c988aeacb1552ca93e4663a7a119"},"schema_version":"1.0","source":{"id":"1811.08259","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1811.08259","created_at":"2026-05-17T23:59:22Z"},{"alias_kind":"arxiv_version","alias_value":"1811.08259v2","created_at":"2026-05-17T23:59:22Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1811.08259","created_at":"2026-05-17T23:59:22Z"},{"alias_kind":"pith_short_12","alias_value":"7ZCIFFHWN443","created_at":"2026-05-18T12:32:13Z"},{"alias_kind":"pith_short_16","alias_value":"7ZCIFFHWN4436DTT","created_at":"2026-05-18T12:32:13Z"},{"alias_kind":"pith_short_8","alias_value":"7ZCIFFHW","created_at":"2026-05-18T12:32:13Z"}],"graph_snapshots":[{"event_id":"sha256:4762689f67dbce7155c8fe71235dbde8a7a37fcf8e9f47c690bb7472f7c22eae","target":"graph","created_at":"2026-05-17T23:59:22Z","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 show that the spectrum of a flow field can be extracted within a local region by straightforward filtering in physical space. We find that for a flow with a certain level of regularity, the filtering kernel must have a sufficient number of vanishing moments in order for the \"filtering spectrum\" to be meaningful. Our derivation follows a similar analysis by Perrier et al. 1995 for the wavelet spectrum, where we show that the filtering kernel has to have at least $p$ vanishing moments in order to correctly extract a spectrum $k^{-\\alpha}$ with $\\alpha < p+2$. For example, any flow with a spec","authors_text":"Hussein Aluie, Mahmoud Sadek","cross_cats":["physics.ao-ph"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.flu-dyn","submitted_at":"2018-11-20T14:17:48Z","title":"Extracting the Spectrum by Spatial Filtering"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1811.08259","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":"sha256:38693257f7f02a22c84d00a55e2451053446db9c2da7202da092be9f6efe95a2","target":"record","created_at":"2026-05-17T23:59:22Z","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":"a713e71462407a8ae35d30bc8b89a4dfe65dd8034b62959ded266e50eee85106","cross_cats_sorted":["physics.ao-ph"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.flu-dyn","submitted_at":"2018-11-20T14:17:48Z","title_canon_sha256":"cef0b265bcedc739b532d41646fbf4b09c35c988aeacb1552ca93e4663a7a119"},"schema_version":"1.0","source":{"id":"1811.08259","kind":"arxiv","version":2}},"canonical_sha256":"fe448294f66f39bf0e7356cb0e4d1d53aaba05d8d54a89d6fe1337015e98a620","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"fe448294f66f39bf0e7356cb0e4d1d53aaba05d8d54a89d6fe1337015e98a620","first_computed_at":"2026-05-17T23:59:22.000786Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-17T23:59:22.000786Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"466v6eubY1Ox92hGs5goImyKmQ7JbxpEJ4mysE1VlKK2GIIcGfJO9m7741B3DW5d4ICZM4ze9dc8ghhtTkDoAg==","signature_status":"signed_v1","signed_at":"2026-05-17T23:59:22.001211Z","signed_message":"canonical_sha256_bytes"},"source_id":"1811.08259","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:38693257f7f02a22c84d00a55e2451053446db9c2da7202da092be9f6efe95a2","sha256:4762689f67dbce7155c8fe71235dbde8a7a37fcf8e9f47c690bb7472f7c22eae"],"state_sha256":"348ba94670fd613a4768bc045c41da15009e23ca19c009b4c7d29efbc625358f"}