{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2017:CZ427ANZTJJPRCCJ6JPNQGUI3N","short_pith_number":"pith:CZ427ANZ","canonical_record":{"source":{"id":"1710.08753","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"gr-qc","submitted_at":"2017-10-24T13:19:22Z","cross_cats_sorted":["astro-ph.CO"],"title_canon_sha256":"635fcd8a898a3761439ffedffa38e8ba9d1c84627e3d39c5f4d140d2cc9e0125","abstract_canon_sha256":"3225a85abdbfe379c4ad28e7231f73381a814e64a9dd1ed5b2e5c309342908ed"},"schema_version":"1.0"},"canonical_sha256":"1679af81b99a52f88849f25ed81a88db69ae0cee8bada9b660fb40842d3314c7","source":{"kind":"arxiv","id":"1710.08753","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1710.08753","created_at":"2026-05-18T00:16:30Z"},{"alias_kind":"arxiv_version","alias_value":"1710.08753v1","created_at":"2026-05-18T00:16:30Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1710.08753","created_at":"2026-05-18T00:16:30Z"},{"alias_kind":"pith_short_12","alias_value":"CZ427ANZTJJP","created_at":"2026-05-18T12:31:10Z"},{"alias_kind":"pith_short_16","alias_value":"CZ427ANZTJJPRCCJ","created_at":"2026-05-18T12:31:10Z"},{"alias_kind":"pith_short_8","alias_value":"CZ427ANZ","created_at":"2026-05-18T12:31:10Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2017:CZ427ANZTJJPRCCJ6JPNQGUI3N","target":"record","payload":{"canonical_record":{"source":{"id":"1710.08753","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"gr-qc","submitted_at":"2017-10-24T13:19:22Z","cross_cats_sorted":["astro-ph.CO"],"title_canon_sha256":"635fcd8a898a3761439ffedffa38e8ba9d1c84627e3d39c5f4d140d2cc9e0125","abstract_canon_sha256":"3225a85abdbfe379c4ad28e7231f73381a814e64a9dd1ed5b2e5c309342908ed"},"schema_version":"1.0"},"canonical_sha256":"1679af81b99a52f88849f25ed81a88db69ae0cee8bada9b660fb40842d3314c7","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T00:16:30.785369Z","signature_b64":"1yVL6CE20LbCEqYoTiJPNb9PjeBewvDsVuEjNSwz2kmVwGilII7dDW4nf4OjCw0JOJPAV2LAid8Y56NVXlQPCA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"1679af81b99a52f88849f25ed81a88db69ae0cee8bada9b660fb40842d3314c7","last_reissued_at":"2026-05-18T00:16:30.784872Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T00:16:30.784872Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1710.08753","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":"2026-05-18T00:16:30Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"GsBm9uU6FSd7cmKHNCoKHu36ioYcfjrN2Bv3jPfI1rKdGHfvEIUBFt5N8RHMONZNbxkNgvNEDEXDvwBP9eRyAg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-19T22:18:05.515342Z"},"content_sha256":"fd738aeda3135be05980c57b986c320a325c78c4a1cd184ae00f9b21a2df7278","schema_version":"1.0","event_id":"sha256:fd738aeda3135be05980c57b986c320a325c78c4a1cd184ae00f9b21a2df7278"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2017:CZ427ANZTJJPRCCJ6JPNQGUI3N","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Anisotropic cosmological solutions in $R + R^2$ gravity","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.CO"],"primary_cat":"gr-qc","authors_text":"Aleksey Toporensky, Alexei A. Starobinsky, Angelo Ricciardone, Daniel M\\\"uller","submitted_at":"2017-10-24T13:19:22Z","abstract_excerpt":"In this paper we investigate the past evolution of an anisotropic Bianchi I universe in $R+R^2$ gravity. Using the dynamical system approach we show that there exists a new two-parameters set of solutions that includes both an isotropic \"false radiation\" solution and an anisotropic generalized Kasner solution, which is stable. We derive the analytic behaviour of the shear from a specific property of $f(R)$ gravity and the analytic asymptotic form of the Ricci scalar when approaching the initial singularity. Finally we numerically checked our results."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1710.08753","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":"2026-05-18T00:16:30Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"oE+JOv0R6jw05owFhjhzGQo2iQBBeljP9g+aXT04VZdI5otzOoufoEx11/PRzycuk3xRgMi2yCdZQjPdedwBAw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-19T22:18:05.515715Z"},"content_sha256":"1391890a1382235a3aa22276a2a55b5a93a9f5aa3ee0a7adbf42378b8c27cb4c","schema_version":"1.0","event_id":"sha256:1391890a1382235a3aa22276a2a55b5a93a9f5aa3ee0a7adbf42378b8c27cb4c"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/CZ427ANZTJJPRCCJ6JPNQGUI3N/bundle.json","state_url":"https://pith.science/pith/CZ427ANZTJJPRCCJ6JPNQGUI3N/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/CZ427ANZTJJPRCCJ6JPNQGUI3N/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":"2026-05-19T22:18:05Z","links":{"resolver":"https://pith.science/pith/CZ427ANZTJJPRCCJ6JPNQGUI3N","bundle":"https://pith.science/pith/CZ427ANZTJJPRCCJ6JPNQGUI3N/bundle.json","state":"https://pith.science/pith/CZ427ANZTJJPRCCJ6JPNQGUI3N/state.json","well_known_bundle":"https://pith.science/.well-known/pith/CZ427ANZTJJPRCCJ6JPNQGUI3N/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2017:CZ427ANZTJJPRCCJ6JPNQGUI3N","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":"3225a85abdbfe379c4ad28e7231f73381a814e64a9dd1ed5b2e5c309342908ed","cross_cats_sorted":["astro-ph.CO"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"gr-qc","submitted_at":"2017-10-24T13:19:22Z","title_canon_sha256":"635fcd8a898a3761439ffedffa38e8ba9d1c84627e3d39c5f4d140d2cc9e0125"},"schema_version":"1.0","source":{"id":"1710.08753","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1710.08753","created_at":"2026-05-18T00:16:30Z"},{"alias_kind":"arxiv_version","alias_value":"1710.08753v1","created_at":"2026-05-18T00:16:30Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1710.08753","created_at":"2026-05-18T00:16:30Z"},{"alias_kind":"pith_short_12","alias_value":"CZ427ANZTJJP","created_at":"2026-05-18T12:31:10Z"},{"alias_kind":"pith_short_16","alias_value":"CZ427ANZTJJPRCCJ","created_at":"2026-05-18T12:31:10Z"},{"alias_kind":"pith_short_8","alias_value":"CZ427ANZ","created_at":"2026-05-18T12:31:10Z"}],"graph_snapshots":[{"event_id":"sha256:1391890a1382235a3aa22276a2a55b5a93a9f5aa3ee0a7adbf42378b8c27cb4c","target":"graph","created_at":"2026-05-18T00:16:30Z","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":"In this paper we investigate the past evolution of an anisotropic Bianchi I universe in $R+R^2$ gravity. Using the dynamical system approach we show that there exists a new two-parameters set of solutions that includes both an isotropic \"false radiation\" solution and an anisotropic generalized Kasner solution, which is stable. We derive the analytic behaviour of the shear from a specific property of $f(R)$ gravity and the analytic asymptotic form of the Ricci scalar when approaching the initial singularity. Finally we numerically checked our results.","authors_text":"Aleksey Toporensky, Alexei A. Starobinsky, Angelo Ricciardone, Daniel M\\\"uller","cross_cats":["astro-ph.CO"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"gr-qc","submitted_at":"2017-10-24T13:19:22Z","title":"Anisotropic cosmological solutions in $R + R^2$ gravity"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1710.08753","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:fd738aeda3135be05980c57b986c320a325c78c4a1cd184ae00f9b21a2df7278","target":"record","created_at":"2026-05-18T00:16:30Z","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":"3225a85abdbfe379c4ad28e7231f73381a814e64a9dd1ed5b2e5c309342908ed","cross_cats_sorted":["astro-ph.CO"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"gr-qc","submitted_at":"2017-10-24T13:19:22Z","title_canon_sha256":"635fcd8a898a3761439ffedffa38e8ba9d1c84627e3d39c5f4d140d2cc9e0125"},"schema_version":"1.0","source":{"id":"1710.08753","kind":"arxiv","version":1}},"canonical_sha256":"1679af81b99a52f88849f25ed81a88db69ae0cee8bada9b660fb40842d3314c7","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"1679af81b99a52f88849f25ed81a88db69ae0cee8bada9b660fb40842d3314c7","first_computed_at":"2026-05-18T00:16:30.784872Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T00:16:30.784872Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"1yVL6CE20LbCEqYoTiJPNb9PjeBewvDsVuEjNSwz2kmVwGilII7dDW4nf4OjCw0JOJPAV2LAid8Y56NVXlQPCA==","signature_status":"signed_v1","signed_at":"2026-05-18T00:16:30.785369Z","signed_message":"canonical_sha256_bytes"},"source_id":"1710.08753","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:fd738aeda3135be05980c57b986c320a325c78c4a1cd184ae00f9b21a2df7278","sha256:1391890a1382235a3aa22276a2a55b5a93a9f5aa3ee0a7adbf42378b8c27cb4c"],"state_sha256":"04fa38efdbfb7956ca34587ad495ba29dcc1e3b22cb830eb48abaac4c353631f"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"JLU2ObH85cUN6ml8BTxidAn06MGGWJ6/lweB0rRVgcskA5/P1t7faqiZMOhZcxwzj2omsE8LiU/1qj1bHjKtAQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-19T22:18:05.517652Z","bundle_sha256":"cdd82da3520436041603fe96faffcf26a006de945da3a0c777311351eed9d6fa"}}