{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2026:TQLCBNYLDVDBILXDGTAD5AVTHT","short_pith_number":"pith:TQLCBNYL","canonical_record":{"source":{"id":"2606.18521","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.LG","submitted_at":"2026-06-16T22:22:40Z","cross_cats_sorted":["cs.AI"],"title_canon_sha256":"031e6f7009980e9a4e0a87ff03aeae43d0678992e58c436d4155c787e552e2c4","abstract_canon_sha256":"25a51ee8f8b3c7cbcca2f6e0faba7dacdf4532c27d3f0d3b76d502ca33cedbc7"},"schema_version":"1.0"},"canonical_sha256":"9c1620b70b1d46142ee334c03e82b33cf1f66a1a69a9a3c7e08a19cb63d891f7","source":{"kind":"arxiv","id":"2606.18521","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2606.18521","created_at":"2026-06-19T16:11:39Z"},{"alias_kind":"arxiv_version","alias_value":"2606.18521v1","created_at":"2026-06-19T16:11:39Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2606.18521","created_at":"2026-06-19T16:11:39Z"},{"alias_kind":"pith_short_12","alias_value":"TQLCBNYLDVDB","created_at":"2026-06-19T16:11:39Z"},{"alias_kind":"pith_short_16","alias_value":"TQLCBNYLDVDBILXD","created_at":"2026-06-19T16:11:39Z"},{"alias_kind":"pith_short_8","alias_value":"TQLCBNYL","created_at":"2026-06-19T16:11:39Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2026:TQLCBNYLDVDBILXDGTAD5AVTHT","target":"record","payload":{"canonical_record":{"source":{"id":"2606.18521","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.LG","submitted_at":"2026-06-16T22:22:40Z","cross_cats_sorted":["cs.AI"],"title_canon_sha256":"031e6f7009980e9a4e0a87ff03aeae43d0678992e58c436d4155c787e552e2c4","abstract_canon_sha256":"25a51ee8f8b3c7cbcca2f6e0faba7dacdf4532c27d3f0d3b76d502ca33cedbc7"},"schema_version":"1.0"},"canonical_sha256":"9c1620b70b1d46142ee334c03e82b33cf1f66a1a69a9a3c7e08a19cb63d891f7","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-06-19T16:11:39.920120Z","signature_b64":"r3KcWm7G4UqveeeCIIJ+kL8vj4QRkpPFseP2wLyyDwiq3rLqrxXfwjRD+XALwomcOdZrIm4311mboLoze886CA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"9c1620b70b1d46142ee334c03e82b33cf1f66a1a69a9a3c7e08a19cb63d891f7","last_reissued_at":"2026-06-19T16:11:39.919611Z","signature_status":"signed_v1","first_computed_at":"2026-06-19T16:11:39.919611Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"2606.18521","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":"2026-06-19T16:11:39Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"2gedocrKt8Q7kNRgKBouHO2ABlyQkqDVc8uuUmuZG+gRjSqNleWdIYu9Drd87Pf/dym+1taabhku2NF/djB6Ag==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-07-04T07:35:50.041294Z"},"content_sha256":"baf55fe30e030e18f720d6c7de7c39c943d6108ed6a0f3d0cc78a7f4798394ce","schema_version":"1.0","event_id":"sha256:baf55fe30e030e18f720d6c7de7c39c943d6108ed6a0f3d0cc78a7f4798394ce"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2026:TQLCBNYLDVDBILXDGTAD5AVTHT","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Sparsity Curse: Understanding RLVR Model Parameter Space from Model Merging","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["cs.AI"],"primary_cat":"cs.LG","authors_text":"Chenrui Wu, Haishuai Wang, Jiajun Bu, Jiangchuan Liu, Zexi Li","submitted_at":"2026-06-16T22:22:40Z","abstract_excerpt":"Reinforcement Learning with Verifiable Reward (RLVR) has emerged as a powerful post-training paradigm that surpasses Supervised Fine-Tuning (SFT) in eliciting reasoning intelligence and resisting catastrophic forgetting. Recent studies further reveal that RLVR induces highly sparse and off-principal parameter updates compared to SFT. This naturally raises the question: does such sparsity make RLVR models more amenable to model merging? If so, model merging would offer a scalable, training-free path to aggregate diverse reasoning capabilities from independently trained RLVR models. Surprisingly"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2606.18521","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":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2606.18521/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":"2026-06-19T16:11:39Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"igAafwPAM+DSYGpiUBxbegai7b5Egnf8JXI8bYvw/WzTXcxjPd1R2nJEpmvdr9KtUJGxiEHzOiZzr9Q10eaPCQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-07-04T07:35:50.041693Z"},"content_sha256":"808dce2cd9dc1e303679ee20959e5fbeb8f96260e491e563ef313c6cf2ac59c9","schema_version":"1.0","event_id":"sha256:808dce2cd9dc1e303679ee20959e5fbeb8f96260e491e563ef313c6cf2ac59c9"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/TQLCBNYLDVDBILXDGTAD5AVTHT/bundle.json","state_url":"https://pith.science/pith/TQLCBNYLDVDBILXDGTAD5AVTHT/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/TQLCBNYLDVDBILXDGTAD5AVTHT/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":"2026-07-04T07:35:50Z","links":{"resolver":"https://pith.science/pith/TQLCBNYLDVDBILXDGTAD5AVTHT","bundle":"https://pith.science/pith/TQLCBNYLDVDBILXDGTAD5AVTHT/bundle.json","state":"https://pith.science/pith/TQLCBNYLDVDBILXDGTAD5AVTHT/state.json","well_known_bundle":"https://pith.science/.well-known/pith/TQLCBNYLDVDBILXDGTAD5AVTHT/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2026:TQLCBNYLDVDBILXDGTAD5AVTHT","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":"25a51ee8f8b3c7cbcca2f6e0faba7dacdf4532c27d3f0d3b76d502ca33cedbc7","cross_cats_sorted":["cs.AI"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.LG","submitted_at":"2026-06-16T22:22:40Z","title_canon_sha256":"031e6f7009980e9a4e0a87ff03aeae43d0678992e58c436d4155c787e552e2c4"},"schema_version":"1.0","source":{"id":"2606.18521","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2606.18521","created_at":"2026-06-19T16:11:39Z"},{"alias_kind":"arxiv_version","alias_value":"2606.18521v1","created_at":"2026-06-19T16:11:39Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2606.18521","created_at":"2026-06-19T16:11:39Z"},{"alias_kind":"pith_short_12","alias_value":"TQLCBNYLDVDB","created_at":"2026-06-19T16:11:39Z"},{"alias_kind":"pith_short_16","alias_value":"TQLCBNYLDVDBILXD","created_at":"2026-06-19T16:11:39Z"},{"alias_kind":"pith_short_8","alias_value":"TQLCBNYL","created_at":"2026-06-19T16:11:39Z"}],"graph_snapshots":[{"event_id":"sha256:808dce2cd9dc1e303679ee20959e5fbeb8f96260e491e563ef313c6cf2ac59c9","target":"graph","created_at":"2026-06-19T16:11:39Z","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/2606.18521/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"Reinforcement Learning with Verifiable Reward (RLVR) has emerged as a powerful post-training paradigm that surpasses Supervised Fine-Tuning (SFT) in eliciting reasoning intelligence and resisting catastrophic forgetting. Recent studies further reveal that RLVR induces highly sparse and off-principal parameter updates compared to SFT. This naturally raises the question: does such sparsity make RLVR models more amenable to model merging? If so, model merging would offer a scalable, training-free path to aggregate diverse reasoning capabilities from independently trained RLVR models. Surprisingly","authors_text":"Chenrui Wu, Haishuai Wang, Jiajun Bu, Jiangchuan Liu, Zexi Li","cross_cats":["cs.AI"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.LG","submitted_at":"2026-06-16T22:22:40Z","title":"Sparsity Curse: Understanding RLVR Model Parameter Space from Model Merging"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2606.18521","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:baf55fe30e030e18f720d6c7de7c39c943d6108ed6a0f3d0cc78a7f4798394ce","target":"record","created_at":"2026-06-19T16:11:39Z","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":"25a51ee8f8b3c7cbcca2f6e0faba7dacdf4532c27d3f0d3b76d502ca33cedbc7","cross_cats_sorted":["cs.AI"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.LG","submitted_at":"2026-06-16T22:22:40Z","title_canon_sha256":"031e6f7009980e9a4e0a87ff03aeae43d0678992e58c436d4155c787e552e2c4"},"schema_version":"1.0","source":{"id":"2606.18521","kind":"arxiv","version":1}},"canonical_sha256":"9c1620b70b1d46142ee334c03e82b33cf1f66a1a69a9a3c7e08a19cb63d891f7","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"9c1620b70b1d46142ee334c03e82b33cf1f66a1a69a9a3c7e08a19cb63d891f7","first_computed_at":"2026-06-19T16:11:39.919611Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-06-19T16:11:39.919611Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"r3KcWm7G4UqveeeCIIJ+kL8vj4QRkpPFseP2wLyyDwiq3rLqrxXfwjRD+XALwomcOdZrIm4311mboLoze886CA==","signature_status":"signed_v1","signed_at":"2026-06-19T16:11:39.920120Z","signed_message":"canonical_sha256_bytes"},"source_id":"2606.18521","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:baf55fe30e030e18f720d6c7de7c39c943d6108ed6a0f3d0cc78a7f4798394ce","sha256:808dce2cd9dc1e303679ee20959e5fbeb8f96260e491e563ef313c6cf2ac59c9"],"state_sha256":"7e6f88b2eb2e1ab584ce78ae6e94a0bdfec8541ff3bbf10d4231e9068e043e98"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"/qBO7WtNCupOwK2Ufgr0XJa+o549GR0WYFJixf9yfc2QvG5WrlE9VDiinqaFgJam+htb5faALRHMnI6yxpEqDA==","signed_message":"bundle_sha256_bytes","signed_at":"2026-07-04T07:35:50.043652Z","bundle_sha256":"dcac6fc14dd98544a029e9da49fa71b58ac596c59c664d1b22a10b219b3ccd7b"}}