{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2009:K5F4I4CIIMGMLA44MJF23CQWCD","short_pith_number":"pith:K5F4I4CI","canonical_record":{"source":{"id":"0908.2457","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2009-08-17T22:32:07Z","cross_cats_sorted":[],"title_canon_sha256":"737473769f46a0b755b2d31f3e76bd8a4fe481c6dce4ec822ce01c636de15a9a","abstract_canon_sha256":"1462aeb2f9e0f99784b307dd915b4edce7298a8ffa635d9bf1024b55154ff93f"},"schema_version":"1.0"},"canonical_sha256":"574bc47048430cc5839c624bad8a1610f7de7ec95047b0d5ec3367185dc65ac1","source":{"kind":"arxiv","id":"0908.2457","version":2},"source_aliases":[{"alias_kind":"arxiv","alias_value":"0908.2457","created_at":"2026-07-04T16:21:51Z"},{"alias_kind":"arxiv_version","alias_value":"0908.2457v2","created_at":"2026-07-04T16:21:51Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.0908.2457","created_at":"2026-07-04T16:21:51Z"},{"alias_kind":"pith_short_12","alias_value":"K5F4I4CIIMGM","created_at":"2026-07-04T16:21:51Z"},{"alias_kind":"pith_short_16","alias_value":"K5F4I4CIIMGMLA44","created_at":"2026-07-04T16:21:51Z"},{"alias_kind":"pith_short_8","alias_value":"K5F4I4CI","created_at":"2026-07-04T16:21:51Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2009:K5F4I4CIIMGMLA44MJF23CQWCD","target":"record","payload":{"canonical_record":{"source":{"id":"0908.2457","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2009-08-17T22:32:07Z","cross_cats_sorted":[],"title_canon_sha256":"737473769f46a0b755b2d31f3e76bd8a4fe481c6dce4ec822ce01c636de15a9a","abstract_canon_sha256":"1462aeb2f9e0f99784b307dd915b4edce7298a8ffa635d9bf1024b55154ff93f"},"schema_version":"1.0"},"canonical_sha256":"574bc47048430cc5839c624bad8a1610f7de7ec95047b0d5ec3367185dc65ac1","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-04T16:21:51.617806Z","signature_b64":"d+zF+YaZjty/ot84WtgsdCSk9A08idilbv++AtMiPw52T8iy3ZYdmDeIT29Nzp8pZgGwawRwViBjspE90n/yCw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"574bc47048430cc5839c624bad8a1610f7de7ec95047b0d5ec3367185dc65ac1","last_reissued_at":"2026-07-04T16:21:51.617409Z","signature_status":"signed_v1","first_computed_at":"2026-07-04T16:21:51.617409Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"0908.2457","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":"2026-07-04T16:21:51Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"nKBqbHp3aHg4CT0r5qB/XSt+lPc/wQyAiUeMr0C7p0+w52VvdQFMhPU+cKysbMyltPGIKKKnxGnQfND04We1DQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-07T05:37:23.055335Z"},"content_sha256":"9b9b5543349eb46bcdb4802677b52d0d50165944b83849ba17fdb11d862cc46c","schema_version":"1.0","event_id":"sha256:9b9b5543349eb46bcdb4802677b52d0d50165944b83849ba17fdb11d862cc46c"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2009:K5F4I4CIIMGMLA44MJF23CQWCD","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Cluster Constraints on f(R) Gravity","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.CO","authors_text":"Alexey Vikhlinin, Fabian Schmidt, Wayne Hu","submitted_at":"2009-08-17T22:32:07Z","abstract_excerpt":"Modified gravitational forces in models that seek to explain cosmic acceleration without dark energy typically predict deviations in the abundance of massive dark matter halos. We conduct the first, simulation calibrated, cluster abundance constraints on a modified gravity model, specifically the modified action f(R) model. The local cluster abundance, when combined with geometric and high redshift data from the cosmic microwave background, supernovae, H_0 and baryon acoustic oscillations, improve previous constraints by nearly 4 orders of magnitude in the field amplitude. These limits corresp"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"0908.2457","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/0908.2457/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":"2026-07-04T16:21:51Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"mWN9xs/YxJ5JQkgYUe4DaqcvSrb9ZdNSL0xG9nNMuACq1mCE9H8OGTvEl1RZbuTmKfo18U8UAxfAHukTx1TDAw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-07T05:37:23.056005Z"},"content_sha256":"83ab8f491089ccb02e651d02e18074df68364b429744f35d47acec5e0e14cb26","schema_version":"1.0","event_id":"sha256:83ab8f491089ccb02e651d02e18074df68364b429744f35d47acec5e0e14cb26"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/K5F4I4CIIMGMLA44MJF23CQWCD/bundle.json","state_url":"https://pith.science/pith/K5F4I4CIIMGMLA44MJF23CQWCD/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/K5F4I4CIIMGMLA44MJF23CQWCD/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":"2026-08-07T05:37:23Z","links":{"resolver":"https://pith.science/pith/K5F4I4CIIMGMLA44MJF23CQWCD","bundle":"https://pith.science/pith/K5F4I4CIIMGMLA44MJF23CQWCD/bundle.json","state":"https://pith.science/pith/K5F4I4CIIMGMLA44MJF23CQWCD/state.json","well_known_bundle":"https://pith.science/.well-known/pith/K5F4I4CIIMGMLA44MJF23CQWCD/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2009:K5F4I4CIIMGMLA44MJF23CQWCD","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":"1462aeb2f9e0f99784b307dd915b4edce7298a8ffa635d9bf1024b55154ff93f","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2009-08-17T22:32:07Z","title_canon_sha256":"737473769f46a0b755b2d31f3e76bd8a4fe481c6dce4ec822ce01c636de15a9a"},"schema_version":"1.0","source":{"id":"0908.2457","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"0908.2457","created_at":"2026-07-04T16:21:51Z"},{"alias_kind":"arxiv_version","alias_value":"0908.2457v2","created_at":"2026-07-04T16:21:51Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.0908.2457","created_at":"2026-07-04T16:21:51Z"},{"alias_kind":"pith_short_12","alias_value":"K5F4I4CIIMGM","created_at":"2026-07-04T16:21:51Z"},{"alias_kind":"pith_short_16","alias_value":"K5F4I4CIIMGMLA44","created_at":"2026-07-04T16:21:51Z"},{"alias_kind":"pith_short_8","alias_value":"K5F4I4CI","created_at":"2026-07-04T16:21:51Z"}],"graph_snapshots":[{"event_id":"sha256:83ab8f491089ccb02e651d02e18074df68364b429744f35d47acec5e0e14cb26","target":"graph","created_at":"2026-07-04T16:21:51Z","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/0908.2457/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"Modified gravitational forces in models that seek to explain cosmic acceleration without dark energy typically predict deviations in the abundance of massive dark matter halos. We conduct the first, simulation calibrated, cluster abundance constraints on a modified gravity model, specifically the modified action f(R) model. The local cluster abundance, when combined with geometric and high redshift data from the cosmic microwave background, supernovae, H_0 and baryon acoustic oscillations, improve previous constraints by nearly 4 orders of magnitude in the field amplitude. These limits corresp","authors_text":"Alexey Vikhlinin, Fabian Schmidt, Wayne Hu","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2009-08-17T22:32:07Z","title":"Cluster Constraints on f(R) Gravity"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"0908.2457","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":"sha256:9b9b5543349eb46bcdb4802677b52d0d50165944b83849ba17fdb11d862cc46c","target":"record","created_at":"2026-07-04T16:21:51Z","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":"1462aeb2f9e0f99784b307dd915b4edce7298a8ffa635d9bf1024b55154ff93f","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2009-08-17T22:32:07Z","title_canon_sha256":"737473769f46a0b755b2d31f3e76bd8a4fe481c6dce4ec822ce01c636de15a9a"},"schema_version":"1.0","source":{"id":"0908.2457","kind":"arxiv","version":2}},"canonical_sha256":"574bc47048430cc5839c624bad8a1610f7de7ec95047b0d5ec3367185dc65ac1","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"574bc47048430cc5839c624bad8a1610f7de7ec95047b0d5ec3367185dc65ac1","first_computed_at":"2026-07-04T16:21:51.617409Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-04T16:21:51.617409Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"d+zF+YaZjty/ot84WtgsdCSk9A08idilbv++AtMiPw52T8iy3ZYdmDeIT29Nzp8pZgGwawRwViBjspE90n/yCw==","signature_status":"signed_v1","signed_at":"2026-07-04T16:21:51.617806Z","signed_message":"canonical_sha256_bytes"},"source_id":"0908.2457","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:9b9b5543349eb46bcdb4802677b52d0d50165944b83849ba17fdb11d862cc46c","sha256:83ab8f491089ccb02e651d02e18074df68364b429744f35d47acec5e0e14cb26"],"state_sha256":"6941dcaf199550ac3a0871d9e87689cea115c16ec21229f60f0e9ce49bb09cc0"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"TTBSvU2hFrtyWiD9DYLj6dqKVIjrZspm5/nHnjbUAgdG2fXHbRYgCOVaCzhTtcGHZIKwnoyccUzE0cMyCNItBw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-08-07T05:37:23.061314Z","bundle_sha256":"58aa76752474cb0da8697bc37e307641383fddeb7f3d8dc505f54ecfb38eb8e0"}}