{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:1998:SCV4T7QVZB2GBFSKMBHPFFQDCE","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":"835e56f5c6c096f375eb80ec94b5ff954c5461ea99fc8db452d7624006230721","cross_cats_sorted":[],"license":"","primary_cat":"gr-qc","submitted_at":"1998-07-29T14:25:29Z","title_canon_sha256":"31a7b5eb0d145fce5c4ac75d91fa1c0ee4e55a71ba94ced9a67de3cca2d6aa8d"},"schema_version":"1.0","source":{"id":"gr-qc/9807081","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"gr-qc/9807081","created_at":"2026-07-04T16:08:50Z"},{"alias_kind":"arxiv_version","alias_value":"gr-qc/9807081v1","created_at":"2026-07-04T16:08:50Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.gr-qc/9807081","created_at":"2026-07-04T16:08:50Z"},{"alias_kind":"pith_short_12","alias_value":"SCV4T7QVZB2G","created_at":"2026-07-04T16:08:50Z"},{"alias_kind":"pith_short_16","alias_value":"SCV4T7QVZB2GBFSK","created_at":"2026-07-04T16:08:50Z"},{"alias_kind":"pith_short_8","alias_value":"SCV4T7QV","created_at":"2026-07-04T16:08:50Z"}],"graph_snapshots":[{"event_id":"sha256:194bee6961f697c0b6cd011c56718e8990004288e03ca67f3c93c9264b67104e","target":"graph","created_at":"2026-07-04T16:08:50Z","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/gr-qc/9807081/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"We investigate a class of impulsive gravitational waves which propagate either in Minkowski or in the (anti-)de Sitter background. These waves are constructed as impulsive members of the Kundt class $P(\\Lambda)$ of non-twisting, non-expanding type N solutions of vacuum Einstein equations with a cosmological constant $\\Lambda$. We show that the only non-trivial waves of this type in Minkowski spacetime are impulsive pp-waves. For $\\Lambda\\not=0$ we demonstrate that the canonical subclasses of $P(\\Lambda)$, which are invariantly different for smooth profiles, are all locally equivalent for impul","authors_text":"J. Podolsky","cross_cats":[],"headline":"","license":"","primary_cat":"gr-qc","submitted_at":"1998-07-29T14:25:29Z","title":"Non-expanding impulsive gravitational waves"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"gr-qc/9807081","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":"sha256:2a077e002fa49b7e4085af1a307ccd1fe82fcacd05a6a78993df07083816fcf5","target":"record","created_at":"2026-07-04T16:08:50Z","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":"835e56f5c6c096f375eb80ec94b5ff954c5461ea99fc8db452d7624006230721","cross_cats_sorted":[],"license":"","primary_cat":"gr-qc","submitted_at":"1998-07-29T14:25:29Z","title_canon_sha256":"31a7b5eb0d145fce5c4ac75d91fa1c0ee4e55a71ba94ced9a67de3cca2d6aa8d"},"schema_version":"1.0","source":{"id":"gr-qc/9807081","kind":"arxiv","version":1}},"canonical_sha256":"90abc9fe15c87460964a604ef29603113605c2448f59843cdb3f6da36b1ad3c3","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"90abc9fe15c87460964a604ef29603113605c2448f59843cdb3f6da36b1ad3c3","first_computed_at":"2026-07-04T16:08:50.734322Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-04T16:08:50.734322Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"yRM96igENfiCyYgmDsrvVFAqrxAEgpq9Byh0M6LjA3pafJCZXyWU7ljZJ/YD3GxIGMfqLLbxeAFmkRlaKVtEAw==","signature_status":"signed_v1","signed_at":"2026-07-04T16:08:50.734701Z","signed_message":"canonical_sha256_bytes"},"source_id":"gr-qc/9807081","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:2a077e002fa49b7e4085af1a307ccd1fe82fcacd05a6a78993df07083816fcf5","sha256:194bee6961f697c0b6cd011c56718e8990004288e03ca67f3c93c9264b67104e"],"state_sha256":"9cce945263ae9e788a3194dbb6d3d381f6f327de3abe7f273da04eab8e82049d"}