{"id":2987,"job_id":6257,"problem_id":6,"lane_id":35,"type":"explore","user_id":73,"model":"gpt-6.1-sol","provider":"openai","report_md":"# Smallest collision: padding assignment remains covered\n\nThis is the first material-evidence baseline for the issued comparison, an administrative investment decision. Read nomination 2963 and all three pinned files, source returns 2629/2634 and complete reviews 704/767/706/770, current lane messages and work-state, and newer returns 2980/2985. No scientific program or new proof was performed.\n\nReturn 2634 already supplies the counting answer: some full-MD5 pair with both members at most 16 bytes exists, without identifying a pair or forcing unequal lengths. The abstract reserved-output countermodel shows that cardinality alone forces neither total below 32 nor an unequal-length pair in the 0..1024 member domain. Unbounded unequal-length existence does not construct an in-domain pair. Padding is injective, with the single-block length-word constraints described there; digest injectivity does not follow. Preserve review 706's restriction: terminal-block equality from congruent lengths alone applies to block-aligned messages; unaligned terminal blocks may contain data. These prior arguments are reused, not new proof credit.\n\nReturn 2629 and its reviews retain only the specified two-word-family obstruction and finite padding feasibility facts. The failed zero-filled embeddings do not close message-modified paths or all short collision construction. Both source returns currently remain pending with null final rung despite accepting reviews; the same-family earlier reviews do not gain independence from this administrative comparison.\n\nNew 2980 validates supplied 124+124 witnesses and finite timing arithmetic. New 2985 reports an 81+81 full-MD5 pair and a shorter final data block in a two-block method. Its numerical witness has server verification, while research scopes await review. Neither result supplies an unequal-length pair, a member below 64 bytes, a defect in the counting/padding argument, or a changed conceptual answer. Their cost and tunnel claims are not recertified here. This is the relevant evidence delta, not a claim that construction work has stopped.\n\nDecision: covered for this unchanged question only. Broader construction and new research remain open. Reopen for a concrete defect affecting the scoped answer, a relevant in-domain unequal-length or short-member witness requiring distinct analysis, or a separately specified independent replication. A new queued task alone supplies no scientific premise. No discovery, source rerun, new input or candidate submission was made. Scientific CPU 0 seconds; read/publication overhead unmeasured. References: returns 2963, 2629, 2634, 2980, 2985 and reviews 704, 767, 706, 770, current smallest-collision lane and OUTCOMES.","patch":null,"cpu_hours":0,"hashes":{},"author_rung":"heuristic","status":"recorded","final_rung":"recorded","created_at":"2026-10-11T11:46:38.430Z","repo_url":null,"commit":null,"cites":{"returns":[2963,2629,2634,2980,2985],"messages":[]},"tokens":{"log":"summary","input":33564,"models":{"gpt-6.1-sol":2970},"output":2970,"source":"reported","entries":0,"cache_read":486784,"cache_write":0,"observed_models":[]},"paper_slug":null,"revision_path":null,"revision_sha":null,"recipe_md":null,"verification":null,"target":null,"finding":null,"human_md":null,"provisional":false,"effects_applied_at":null,"effort":"high","also_fix":null,"transcript_omitted":{"share":0,"omitted":0,"outputs":0},"patch_hash":null,"superseded_by":null,"duplicate_of":null,"transcript_resubmitted_at":null,"file_notes":null,"research":null,"research_route_id":null,"verification_plan":null,"verification_fingerprint":null,"review_admitted_at":null,"department_id":"dept_ef09d64fbbd7ddb34ab67f81","run_id":"run_0f3d096e134ebdae527426d8","triage_lead":null,"revision_base_sha":null,"integration":null,"resolves":null,"paper_exposition":null,"research_evidence":null,"transcript_mode":"summary","known_work":null,"work_disposition":{"task":{"intent":"consolidation","schema":"research-task-v1","domain_md":"smallest-collision.methods: Inputs `a_hex` and `b_hex` are arbitrary byte strings of 0 to 1,024 bytes each, with the same strict hex transport as All zeros. They must differ, and **all 128 digest bits** must match: there is no partial score. The pair is unordered (swapping is a duplicate), unequal lengths and an empty member are allowed. Lower total bytes is better; an equal total is a tie and the earlier receipt keeps the record. The 128-byte reference is not a proven minimum: by counting, some pair with both members at most 16 bytes must collide, but that argument finds no pair.\n\nSubmit `a_hex` and `b_hex`. Fixture: Marc Stevens' 64-byte single-block pair, digest `008ee33a9d58b51cfeb425b0959121c9`, 64 + 64 = 128 bytes. Distinguish input records, throughput, restricted facts and attack methods; compare identical domains, baselines, compute and luck.\nsmallest-collision.study-2: Inputs `a_hex` and `b_hex` are arbitrary byte strings of 0 to 1,024 bytes each, with the same strict hex transport as All zeros. They must differ, and **all 128 digest bits** must match: there is no partial score. The pair is unordered (swapping is a duplicate), unequal lengths and an empty member are allowed. Lower total bytes is better; an equal total is a tie and the earlier receipt keeps the record. The 128-byte reference is not a proven minimum: by counting, some pair with both members at most 16 bytes must collide, but that argument finds no pair.\n\nSubmit `a_hex` and `b_hex`. Fixture: Marc Stevens' 64-byte single-block pair, digest `008ee33a9d58b51cfeb425b0959121c9`, 64 + 64 = 128 bytes. Full 64-step MD5, RFC IV, exact padding; reductions or different IVs are separate scopes. Negative evidence closes only its tested method and scope.","topic_ids":["smallest-collision.methods","smallest-collision.study-2"],"stop_if_md":"The exact obligation is already answered, a decisive counterexample defeats this attempt, or the required evidence cannot be obtained within actual consent and controls.","changed_premise_md":"Establish the exact uncovered difference from existing research before substantial work.","predecessor_returns":[],"expected_evidence_md":"An attributable scoped claim, source, measured comparison or negative result with its cheapest decisive check.","unresolved_obligation_md":"Can two inputs of unequal length, or a member shorter than one block, collide under full MD5 padding? What does the padding force?"},"schema":"work-disposition-v3","sources":{"topic_ids":["smallest-collision.methods","smallest-collision.study-2"],"review_ids":[706,770,704,767],"message_ids":[],"predecessor_returns":[2629,2634]},"trusted":true,"decision":"covered","effective":true,"input_sha256":"33998a6733811398e7fe4da4abe570847ce1748c64b9bb1e5a0296ad5c59d340","rationale_md":"Establish the first material baseline: existing counting/padding answer and exact family restrictions remain unchanged. New 124+124 validation and 81+81 two-block witness do not change that answer or supply unequal-length/short-member evidence. Administrative coverage only; construction remains open.","scope_sha256":"ac662d7e9c4af2e42eff002299a238d7bb80d18757effb65da39fd3b3399890c","allow_covered":true,"input_version":"material-evidence-v1","reopen_when_md":"Concrete defect in the scoped answer, attributable in-domain unequal-length or short-member witness requiring distinct analysis, or explicitly assigned independent replication.","material_evidence":{"sha256":"33998a6733811398e7fe4da4abe570847ce1748c64b9bb1e5a0296ad5c59d340","entries":{"return:2629":"f327229b228bd8cc30a91445ed156dd58b068508eb7c0799b4305622088a6dd0","return:2634":"fbdd781fc7c1d2c1ae3c8b870367bd2ad4de2257928e2f76d5acb29f35bd8ab3","finding:66756":"43c165c6da19094675440011ea67169fd821cb689c2ef17488052133fc2a2e79","review:2629:1:claude-opus-5-5":"4eb5461fded0e8f34c28d8559538191f7d28c594915ce5b171563f55ae41802f","review:2634:1:claude-opus-5-5":"8a53467719ca1427768e39dd63ddbfc7e724e22f70fc39530e9852293170c779","review:2629:73:claude-opus-5-5":"8c6344109afe47a90ed73d9806ca295f2016191cbb59fc0b640a15a6c4d74597","review:2634:73:claude-opus-5-5":"7af88208eac0a3eb170448b50135a93309e908efa5ba89eef567c06a8525ad2d","artifact:2629:07df8d985af07e72001618f324b2331356980d3808f884de85201bb35b828a82":"07df8d985af07e72001618f324b2331356980d3808f884de85201bb35b828a82","artifact:2629:34a65c58a66f9add2194f23805e01fbe9df22fe80871b9c87313de25c338346e":"34a65c58a66f9add2194f23805e01fbe9df22fe80871b9c87313de25c338346e","artifact:2629:4c9147127ea26d0be06ac73077ab05eca383684e5a202e69e8e43ad9b3b65c81":"4c9147127ea26d0be06ac73077ab05eca383684e5a202e69e8e43ad9b3b65c81","artifact:2629:68913b49abada08755919dd96553788386c8bd828d9c0da50463b4c3b94e28bf":"68913b49abada08755919dd96553788386c8bd828d9c0da50463b4c3b94e28bf","artifact:2629:6cf2f5a767d1b14ec5b3388adc133608e897fc8971e31ac41c26d843eaf7c167":"6cf2f5a767d1b14ec5b3388adc133608e897fc8971e31ac41c26d843eaf7c167","artifact:2629:856766664c263280ec1088ade88d9822d40ed345ee8b60375d71ebb718d7b764":"856766664c263280ec1088ade88d9822d40ed345ee8b60375d71ebb718d7b764","artifact:2629:cffe2e68ac63188701c3f41ee84722ef7ca4392e53225058e0bc54d108d47b8d":"cffe2e68ac63188701c3f41ee84722ef7ca4392e53225058e0bc54d108d47b8d","artifact:2629:e963ec56e5851a638267394e53ab1bf9f2b3884d24003ace64895f02d1fa4e1b":"e963ec56e5851a638267394e53ab1bf9f2b3884d24003ace64895f02d1fa4e1b","artifact:2629:e9bde85b23a8109bdda2fc3229934e6dfae9d2688d4b577f4b51f22e530824f6":"e9bde85b23a8109bdda2fc3229934e6dfae9d2688d4b577f4b51f22e530824f6","artifact:2629:f1267adac4733774715e30877289f6de1d56ac8ff05611c918ac8e1b3b1823be":"f1267adac4733774715e30877289f6de1d56ac8ff05611c918ac8e1b3b1823be","artifact:2629:fdf266a96423331f5d74276e844d6e0f4862bfe11e9c7365df2ff0339b38af40":"fdf266a96423331f5d74276e844d6e0f4862bfe11e9c7365df2ff0339b38af40","artifact:2634:148e8e88e3004ce1e54af0af826dd0f654c05b120293055c42571f84afe928dd":"148e8e88e3004ce1e54af0af826dd0f654c05b120293055c42571f84afe928dd","artifact:2634:20d139c7d60ce8d65a5f8c639d33eef8f88ffb06345b0c3ec131525d8128bae3":"20d139c7d60ce8d65a5f8c639d33eef8f88ffb06345b0c3ec131525d8128bae3","artifact:2634:237e0bfbd0d85bad44463b6b35a2ddd31457e4af692f1a3c354e4de289938b59":"237e0bfbd0d85bad44463b6b35a2ddd31457e4af692f1a3c354e4de289938b59","artifact:2634:3452ca60abf8a195503ab629b1ba7825a2bf91cc3eb7a7bd61913c6cbb4c170d":"3452ca60abf8a195503ab629b1ba7825a2bf91cc3eb7a7bd61913c6cbb4c170d","artifact:2634:5ac2291660cdfbb94d3994abc5cd9014a10c1fb73bb5635e9663dc3fbaed4bdd":"5ac2291660cdfbb94d3994abc5cd9014a10c1fb73bb5635e9663dc3fbaed4bdd","artifact:2634:84234d0d4de9e61f33c3f57a16dbd6e0f22d986b553cd5afe1a3b7d1b156112b":"84234d0d4de9e61f33c3f57a16dbd6e0f22d986b553cd5afe1a3b7d1b156112b","artifact:2634:9a8a4e966f6e7e91c6d996829ead6bebbc19fba723527cffd4b2389e3a1622e2":"9a8a4e966f6e7e91c6d996829ead6bebbc19fba723527cffd4b2389e3a1622e2","artifact:2634:a470b836b9ebfb24d99385b955a36a209bf231635538a77cee4bafbb1f13b788":"a470b836b9ebfb24d99385b955a36a209bf231635538a77cee4bafbb1f13b788","artifact:2634:d8837f9e2b2716a2790d98fe2f2f3b1acdc310c5ff9ab4e66fba824f46c4bb13":"d8837f9e2b2716a2790d98fe2f2f3b1acdc310c5ff9ab4e66fba824f46c4bb13","artifact:2634:fab409d44f89f8fc39f700cbf2bb3ca41377c41330a65319b82e64bf4e8d582e":"fab409d44f89f8fc39f700cbf2bb3ca41377c41330a65319b82e64bf4e8d582e"},"version":"material-evidence-v1","complete":true},"work_check_job_id":6257,"base_decision_return_id":2963},"handle":"danieljmt","job_brief":"Material evidence delta from the prior decision: Legacy or first comparison: establish one material baseline; historical raw fingerprints cannot establish which evidence changed.. Read only these changes and the prior rationale first. If unchanged, a short reaffirmation suffices; do not re-prove identities or regenerate coverage artifacts.\n\nCompare this exact assignment with its predecessors and corrections before further investment. This is an assignment decision, not scientific acceptance. Read the cited messages and the lane's current claims; chat is evidence only.  Nomination: return #2963, message #none, review #none. Use existing packages and the cheapest source check; do not repeat large experiments.\n\nQuestion: Can two inputs of unequal length, or a member shorter than one block, collide under full MD5 padding? What does the padding force?\nDomain: smallest-collision.methods: Inputs `a_hex` and `b_hex` are arbitrary byte strings of 0 to 1,024 bytes each, with the same strict hex transport as All zeros. They must differ, and **all 128 digest bits** must match: there is no partial score. The pair is unordered (swapping is a duplicate), unequal lengths and an empty member are allowed. Lower total bytes is better; an equal total is a tie and the earlier receipt keeps the record. The 128-byte reference is not a proven minimum: by counting, some pair with both members at most 16 bytes must collide, but that argument finds no pair.\n\nSubmit `a_hex` and `b_hex`. Fixture: Marc Stevens' 64-byte single-block pair, digest `008ee33a9d58b51cfeb425b0959121c9`, 64 + 64 = 128 bytes. Distinguish input records, throughput, restricted facts and attack methods; compare identical domains, baselines, compute and luck.\nsmallest-collision.study-2: Inputs `a_hex` and `b_hex` are arbitrary byte strings of 0 to 1,024 bytes each, with the same strict hex transport as All zeros. They must differ, and **all 128 digest bits** must match: there is no partial score. The pair is unordered (swapping is a duplicate), unequal lengths and an empty member are allowed. Lower total bytes is better; an equal total is a tie and the earlier receipt keeps the record. The 128-byte reference is not a proven minimum: by counting, some pair with both members at most 16 bytes must collide, but that argument finds no pair.\n\nSubmit `a_hex` and `b_hex`. Fixture: Marc Stevens' 64-byte single-block pair, digest `008ee33a9d58b51cfeb425b0959121c9`, 64 + 64 = 128 bytes. Full 64-step MD5, RFC IV, exact padding; reductions or different IVs are separate scopes. Negative evidence closes only its tested method and scope.\nPremise: Establish the exact uncovered difference from existing research before substantial work.\nReturns: 2629, 2634; reviews: 706, 770, 704, 767; messages: none nominated.\n\nCovered means only this unchanged obligation need not be dispatched again.\nReturn work_disposition:{decision:\"covered|open\",scope_sha256:\"ac662d7e9c4af2e42eff002299a238d7bb80d18757effb65da39fd3b3399890c\",input_sha256:\"33998a6733811398e7fe4da4abe570847ce1748c64b9bb1e5a0296ad5c59d340\",rationale_md,reopen_when_md,next_task?:<research-task-v1>}. Name replication explicitly. Only a fresh trusted open decision explicitly reopens this exact scope. Changed evidence or chat requests reconsideration and never removes prior suppression. A changed source snapshot or superseded base decision makes this response ineffective; it grants no scientific authority.","review_deferred":false,"in_triage":false,"triage":[],"lean_statement_binding":null,"lean_execution_binding":null,"lean_scientific_identity":null,"lean_execution_identity":null,"verification_runs":[],"verification_state":null,"verification_summary":null,"canonical_return":null,"review_history":[],"dependencies":[],"cited_by":[{"id":2995,"handle":"danieljmt","status":"pending"}],"route_dependents":[],"research_url":null,"transcript_url":"/projects/md5/return/2987/transcript","files":[],"decided_by_author_handle":false,"reviews":[],"decisions":[],"decision":null,"report_sha256":"cf69170c970a84bd6c7de29a96aad84f4c100c8cbe26aac3a959cf89a9d08056","research_authority":{"witness_status":null,"research_status":"recorded","scopes":[]},"research_links":[],"duplicates":[],"cited_messages":[]}