{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2025:E7MMSI7GSX4OVAFWCIITG7VYT2","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":"f72a7f70afb9216464d3bc5af900479e600a68fd63d3db2486495624268e26b5","cross_cats_sorted":["cs.AI","cs.CR","cs.LG"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.CL","submitted_at":"2025-05-22T16:02:10Z","title_canon_sha256":"bbe0f880d6b00af688249c11a48143cb6e78f53494201a093247912f638998b0"},"schema_version":"1.0","source":{"id":"2505.16831","kind":"arxiv","version":3}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2505.16831","created_at":"2026-05-20T00:02:50Z"},{"alias_kind":"arxiv_version","alias_value":"2505.16831v3","created_at":"2026-05-20T00:02:50Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2505.16831","created_at":"2026-05-20T00:02:50Z"},{"alias_kind":"pith_short_12","alias_value":"E7MMSI7GSX4O","created_at":"2026-05-20T00:02:50Z"},{"alias_kind":"pith_short_16","alias_value":"E7MMSI7GSX4OVAFW","created_at":"2026-05-20T00:02:50Z"},{"alias_kind":"pith_short_8","alias_value":"E7MMSI7G","created_at":"2026-05-20T00:02:50Z"}],"graph_snapshots":[{"event_id":"sha256:9c5030f507e4be629e66834c91658ac96f1e838c68e5d122d3d2ba9453311424","target":"graph","created_at":"2026-05-20T00:02:50Z","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/2505.16831/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"Unlearning in large language models (LLMs) aims to remove specified data, but its efficacy is typically assessed with task-level metrics like accuracy and perplexity. We show that these metrics can be misleading, as models can appear to forget while their original behavior is easily restored through minimal fine-tuning. This \\emph{reversibility} suggests that information is merely suppressed, not genuinely erased. To address this critical evaluation gap, we introduce a \\emph{representation-level analysis framework}. Our toolkit comprises PCA similarity and shift, centered kernel alignment (CKA","authors_text":"Haibo Hu, Huadi Zheng, Minxin Du, Peizhao Hu, Qingqing Ye, Xiang Yue, Xiaoyu Xu, Yang Liu","cross_cats":["cs.AI","cs.CR","cs.LG"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.CL","submitted_at":"2025-05-22T16:02:10Z","title":"Unlearning Isn't Deletion: Investigating Reversibility of Machine Unlearning in LLMs"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2505.16831","kind":"arxiv","version":3},"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:fdd592e46266a29fde1744002dea1a2af9a44330b712a3306f7510581a733a8b","target":"record","created_at":"2026-05-20T00:02:50Z","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":"f72a7f70afb9216464d3bc5af900479e600a68fd63d3db2486495624268e26b5","cross_cats_sorted":["cs.AI","cs.CR","cs.LG"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.CL","submitted_at":"2025-05-22T16:02:10Z","title_canon_sha256":"bbe0f880d6b00af688249c11a48143cb6e78f53494201a093247912f638998b0"},"schema_version":"1.0","source":{"id":"2505.16831","kind":"arxiv","version":3}},"canonical_sha256":"27d8c923e695f8ea80b61211337eb89ebb19182127627d63e3125f9af5767ad5","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"27d8c923e695f8ea80b61211337eb89ebb19182127627d63e3125f9af5767ad5","first_computed_at":"2026-05-20T00:02:50.464419Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-20T00:02:50.464419Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"GSsNwTsUu88MoUeVQ70DY+ubhbWv2awGbbaU98FHDZZJAERzElRi0MMxAA/UofFjTHtt3OqwHWsdjbttujJvCg==","signature_status":"signed_v1","signed_at":"2026-05-20T00:02:50.465336Z","signed_message":"canonical_sha256_bytes"},"source_id":"2505.16831","source_kind":"arxiv","source_version":3}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:fdd592e46266a29fde1744002dea1a2af9a44330b712a3306f7510581a733a8b","sha256:9c5030f507e4be629e66834c91658ac96f1e838c68e5d122d3d2ba9453311424"],"state_sha256":"6f37837dd87658a99db776ff538e0bfa105d962a89478eb25b79aaa31c2eebb9"}