{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2021:V3NMLIAISZ7IN5CO4OPCQV5F4G","short_pith_number":"pith:V3NMLIAI","canonical_record":{"source":{"id":"2108.03260","kind":"arxiv","version":2},"metadata":{"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"astro-ph.CO","submitted_at":"2021-08-06T18:11:56Z","cross_cats_sorted":[],"title_canon_sha256":"bdcece07ba4906eecf80fe179d0e83cc1e45244fdde974634b1d10e9f3c0b54a","abstract_canon_sha256":"dd7e3be61ee2d3039152aebeb4a5382f920a5a1a8beb731d9d2bab817c47f627"},"schema_version":"1.0"},"canonical_sha256":"aedac5a008967e86f44ee39e2857a5e1a37da90aa63b6cd0e98b9874f846d934","source":{"kind":"arxiv","id":"2108.03260","version":2},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2108.03260","created_at":"2026-07-05T05:05:00Z"},{"alias_kind":"arxiv_version","alias_value":"2108.03260v2","created_at":"2026-07-05T05:05:00Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2108.03260","created_at":"2026-07-05T05:05:00Z"},{"alias_kind":"pith_short_12","alias_value":"V3NMLIAISZ7I","created_at":"2026-07-05T05:05:00Z"},{"alias_kind":"pith_short_16","alias_value":"V3NMLIAISZ7IN5CO","created_at":"2026-07-05T05:05:00Z"},{"alias_kind":"pith_short_8","alias_value":"V3NMLIAI","created_at":"2026-07-05T05:05:00Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2021:V3NMLIAISZ7IN5CO4OPCQV5F4G","target":"record","payload":{"canonical_record":{"source":{"id":"2108.03260","kind":"arxiv","version":2},"metadata":{"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"astro-ph.CO","submitted_at":"2021-08-06T18:11:56Z","cross_cats_sorted":[],"title_canon_sha256":"bdcece07ba4906eecf80fe179d0e83cc1e45244fdde974634b1d10e9f3c0b54a","abstract_canon_sha256":"dd7e3be61ee2d3039152aebeb4a5382f920a5a1a8beb731d9d2bab817c47f627"},"schema_version":"1.0"},"canonical_sha256":"aedac5a008967e86f44ee39e2857a5e1a37da90aa63b6cd0e98b9874f846d934","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-05T05:05:00.506590Z","signature_b64":"A3s7YTr6R2MPO10DrMA69blvpBtrblaZfGI7Zp0PP6dhYaW7XWWr1MGoY53QS7RY6ny/fF7C5chxtByT+iOnAg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"aedac5a008967e86f44ee39e2857a5e1a37da90aa63b6cd0e98b9874f846d934","last_reissued_at":"2026-07-05T05:05:00.506144Z","signature_status":"signed_v1","first_computed_at":"2026-07-05T05:05:00.506144Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"2108.03260","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":"2026-07-05T05:05:00Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"PcV7m0HS3IybUSqJB2MidryhjOKvBK6OkgxaIPS6Vhe5VyTDCsymqYyUbbRvNYnwaUfXbcr3WLtGZ55XB6t4CQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-11T02:57:41.880820Z"},"content_sha256":"1f8983383c743889338dd9eec55d4a3297e03aa3a4533e84c30a810afc300582","schema_version":"1.0","event_id":"sha256:1f8983383c743889338dd9eec55d4a3297e03aa3a4533e84c30a810afc300582"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2021:V3NMLIAISZ7IN5CO4OPCQV5F4G","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"The growth of fluctuations in Chaplygin gas cosmologies: A nonlinear Jeans scale for unified dark matter","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.CO","authors_text":"Abdelrahman Abdullah, Ali Ellithi, Amr El-Zant","submitted_at":"2021-08-06T18:11:56Z","abstract_excerpt":"Unified dark matter cosmologies economically combine missing matter and energy in a single fluid. Of these models, the standard Chaplygin gas is theoretically motivated, but faces problems in explaining large scale structure if linear perturbations are directly imposed on the homogeneous fluid. However, early formation of a clustered component of small halos is sufficient (and necessary) for hierarchical clustering to proceed in a CDM-like component as in the standard scenario, with the remaining homogeneous component acting as dark energy. We examine this possibility. A linear analysis shows "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2108.03260","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":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2108.03260/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":"2026-07-05T05:05:00Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"+e3xkyHS7zZJcoaDnQsaRMUDgDyM8JozsDqZcWwPd5+hFhKRlTQUQuW7RBTOGVNVyNtbLkBDBjoWL0HO1ctDDg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-11T02:57:41.881312Z"},"content_sha256":"70809c95e730c01e4273a950772470625ca1e5cd61c5d9e7bccda7a02126cbd5","schema_version":"1.0","event_id":"sha256:70809c95e730c01e4273a950772470625ca1e5cd61c5d9e7bccda7a02126cbd5"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/V3NMLIAISZ7IN5CO4OPCQV5F4G/bundle.json","state_url":"https://pith.science/pith/V3NMLIAISZ7IN5CO4OPCQV5F4G/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/V3NMLIAISZ7IN5CO4OPCQV5F4G/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":"2026-08-11T02:57:41Z","links":{"resolver":"https://pith.science/pith/V3NMLIAISZ7IN5CO4OPCQV5F4G","bundle":"https://pith.science/pith/V3NMLIAISZ7IN5CO4OPCQV5F4G/bundle.json","state":"https://pith.science/pith/V3NMLIAISZ7IN5CO4OPCQV5F4G/state.json","well_known_bundle":"https://pith.science/.well-known/pith/V3NMLIAISZ7IN5CO4OPCQV5F4G/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2021:V3NMLIAISZ7IN5CO4OPCQV5F4G","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":"dd7e3be61ee2d3039152aebeb4a5382f920a5a1a8beb731d9d2bab817c47f627","cross_cats_sorted":[],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"astro-ph.CO","submitted_at":"2021-08-06T18:11:56Z","title_canon_sha256":"bdcece07ba4906eecf80fe179d0e83cc1e45244fdde974634b1d10e9f3c0b54a"},"schema_version":"1.0","source":{"id":"2108.03260","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2108.03260","created_at":"2026-07-05T05:05:00Z"},{"alias_kind":"arxiv_version","alias_value":"2108.03260v2","created_at":"2026-07-05T05:05:00Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2108.03260","created_at":"2026-07-05T05:05:00Z"},{"alias_kind":"pith_short_12","alias_value":"V3NMLIAISZ7I","created_at":"2026-07-05T05:05:00Z"},{"alias_kind":"pith_short_16","alias_value":"V3NMLIAISZ7IN5CO","created_at":"2026-07-05T05:05:00Z"},{"alias_kind":"pith_short_8","alias_value":"V3NMLIAI","created_at":"2026-07-05T05:05:00Z"}],"graph_snapshots":[{"event_id":"sha256:70809c95e730c01e4273a950772470625ca1e5cd61c5d9e7bccda7a02126cbd5","target":"graph","created_at":"2026-07-05T05:05:00Z","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/2108.03260/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"Unified dark matter cosmologies economically combine missing matter and energy in a single fluid. Of these models, the standard Chaplygin gas is theoretically motivated, but faces problems in explaining large scale structure if linear perturbations are directly imposed on the homogeneous fluid. However, early formation of a clustered component of small halos is sufficient (and necessary) for hierarchical clustering to proceed in a CDM-like component as in the standard scenario, with the remaining homogeneous component acting as dark energy. We examine this possibility. A linear analysis shows ","authors_text":"Abdelrahman Abdullah, Ali Ellithi, Amr El-Zant","cross_cats":[],"headline":"","license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"astro-ph.CO","submitted_at":"2021-08-06T18:11:56Z","title":"The growth of fluctuations in Chaplygin gas cosmologies: A nonlinear Jeans scale for unified dark matter"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2108.03260","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":"sha256:1f8983383c743889338dd9eec55d4a3297e03aa3a4533e84c30a810afc300582","target":"record","created_at":"2026-07-05T05:05:00Z","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":"dd7e3be61ee2d3039152aebeb4a5382f920a5a1a8beb731d9d2bab817c47f627","cross_cats_sorted":[],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"astro-ph.CO","submitted_at":"2021-08-06T18:11:56Z","title_canon_sha256":"bdcece07ba4906eecf80fe179d0e83cc1e45244fdde974634b1d10e9f3c0b54a"},"schema_version":"1.0","source":{"id":"2108.03260","kind":"arxiv","version":2}},"canonical_sha256":"aedac5a008967e86f44ee39e2857a5e1a37da90aa63b6cd0e98b9874f846d934","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"aedac5a008967e86f44ee39e2857a5e1a37da90aa63b6cd0e98b9874f846d934","first_computed_at":"2026-07-05T05:05:00.506144Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T05:05:00.506144Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"A3s7YTr6R2MPO10DrMA69blvpBtrblaZfGI7Zp0PP6dhYaW7XWWr1MGoY53QS7RY6ny/fF7C5chxtByT+iOnAg==","signature_status":"signed_v1","signed_at":"2026-07-05T05:05:00.506590Z","signed_message":"canonical_sha256_bytes"},"source_id":"2108.03260","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:1f8983383c743889338dd9eec55d4a3297e03aa3a4533e84c30a810afc300582","sha256:70809c95e730c01e4273a950772470625ca1e5cd61c5d9e7bccda7a02126cbd5"],"state_sha256":"081c01d9a63eeb309e3d2c73bf12dd5b0cf1507055bb01a6bbef902f3e076a55"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"qKqZowVrven7nGhm2wKrfZx6ifxmn3mhagHgS73uNfp88+HaqzT8tPi3diVsrndA3hb5cBOZAdpYw1w5iH/DBg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-08-11T02:57:41.885975Z","bundle_sha256":"5f56e66bf8e39411e380425c0c1835ca5d7d159df61af7604e4d207c43846a7c"}}