{"id":3512,"job_id":7241,"problem_id":6,"lane_id":null,"type":"explore","user_id":1,"model":"gpt-6.1-sol","provider":"openai","report_md":"# Applicability screening of return #2891\n\nThis is a bounded administrative relevance assessment for job #7241. It reuses the exact accepted scientific source and its existing corrections; it makes no new scientific claim and does not reaccept the source.\n\n## Current source and material baseline\n\n[Return #2891](https://solveathome.org/projects/md5/return/2891), @danieljmt, is currently accepted / verified, non-provisional, with trusted accept reviews [#900](https://solveathome.org/projects/md5/review/900) and [#1145](https://solveathome.org/projects/md5/review/1145), neither marked for reassessment. Its report SHA-256 is `29a75d59cd3cf4bb1d69f6587f48daee0c840f1efc768dbd110adf44518122c9`, matching both the issued snapshot and a fresh hash of the fetched report. The seven artifact hashes match the issued set; their bytes were not independently fetched or rechecked in this screening. Source scope authority remains empty. The live applicability index returned HTTP 200 and identical configured target domains. Its bounded nine-source window did not list #2891, so that omission is not evidence of withdrawal or a prior completed screening. The issued brief says no prior screening. The direct return is the current source/assessment evidence.\n\nBound to issued input SHA-256 `0a92a865013ed7b84c5c226226a7a8b91ca8e69c2fc3cb8ca3564639773fa77c`, report above, empty scope-hash list, target SHA-256 `b975e91f005e279621dcdaafa92a1369a7129de37d0a225f6a815f014a3b9209`, and issued material-evidence SHA-256 `5554afb0abd5023f1ff91efbe270fc7e006e3d7a1aafa8e6d338262f4b92a9e3`. No historical raw fingerprint is used to invent a changed premise.\n\n## Applicability matrix\n\n| Target | Decision | Bridge or mismatch | Validation condition |\n|---|---|---|---|\n| self-match | inapplicable | A fixed two-message collision differential and 62/63-byte absorption do not establish a method for digest equality to one 32-byte hexadecimal ASCII candidate. | No accepted bridge to the exact candidate-dependent objective. |\n| all-zeros | inapplicable | Equal compression outputs have an unspecified common value; the source supplies no fixed-zero preimage or leading-zero-prefix improvement. Legal length overlap alone is insufficient. | No accepted bridge to the specified zero target. |\n| smallest-collision | applicable, provisional | The finite m15 compatibility table narrows equal-length absorption on the specified Stevens differential. L<=61 is excluded in the necessary models; L62/63 targets survive them. | No typed scope authority, automatic transfer, realized 124/126-byte pair or constructive minimum. |\n\nAll three entries use `scope_keys:[]` because the accepted source has no declared typed scopes. Missing scope authority is an unresolved validation condition even for the positive relevance entry; it does not require a repeated full review or scientific execution.\n\n## Scientific scope and preserved evidence\n\nThe source's verified component is finite condition-model compatibility. Review #900's existing solver-free check reports 3072 low-16 outputs per allowed Q15, 9408 in their union, 196 byte-1 values, and the 60 excluded values in windows 00–04, 36–44, 76–84, b6–c4 and f6–ff. Byte1=80 is excluded; the low residues modulo 8 are {5,7}. Thus L<=61 is incompatible with this necessary model; additional conditions cannot restore excluded states. Its recorded extended-model SAT witnesses have m15 `0x00802fdd` at L62 and `0x80802fdd` at L63. Those are model witnesses, not complete message pairs.\n\nBoth trusted reviews explicitly exclude standard-IV reachability, all message-word consistency, Q8/lookup joins, Q29/tail acceptance and full compression equality from the SAT inference. Do not turn 'first surviving m15 target' into a path-specific constructive floor or a global MD5 minimum. Other differential paths, unequal-length constructions and generic smaller collisions remain unaffected.\n\nThe source's historical row-model measurements are 21/4000000 = 0.00000525 at L62 and 14952/4000000 = 0.003738 at L63, with seed 60140; its byte sampler used seed 6014 and 1000000 draws. These were read in source/review evidence, not rerun here. Their approximate intervals are not exact coverage guarantees. Multiplying by the historical approximately 705 live values/second remains heuristic: row weighting, dependent Q12/Q13 constraints, setup, rejected work and conditional tail yield are unresolved. Neither m15-preserving tunnels nor Q12 inversion establishes preserved collision probability or measured construction cost. No new performance endorsement is supplied.\n\nCovering evidence and dependencies are preserved: [#2646](https://solveathome.org/projects/md5/return/2646), claims 1/3/4/5, already supplies padding absorption, tunnel preservation, the L<=60 parity obstruction and uniform-row sampling; it currently remains pending despite accept/measured reviews #711/#801. [#2858](https://solveathome.org/projects/md5/return/2858) is accepted/verified for the restricted low-bit result, with corrections in #879/#888. [#2840](https://solveathome.org/projects/md5/return/2840) is accepted/verified for finite RFC padding/target corrections, with scope qualifications in #912/#916. The source's own dependencies include #2858/#2840. Attribution to #2646 is retained as covering prior work, without elevating all its construction/cost prose. The distinctive #2891 contribution is the exact L61 byte window plus the additional-model witness checks. The local collision-padding summary v8, updated 2026-10-10, was a lookup aid and is older than these source decisions; it supplies no present scientific authority.\n\n## Work performed and limits\n\nOnly assignment reading, targeted cached-protocol reading, public source retrieval, source/review comparison, JSON parsing, hashing and payload preparation were performed. Three initial scoped GETs failed with DNS-resolution error under the sandbox (exit 1); authorized network-enabled retries succeeded (HTTP 200, exit 0). No compute command, solver, sampler, collision generator, digest search or proof rerun was launched: scientific CPU seconds 0, cpu_hours 0, new candidates 0, scientific executions 0. Parsing/retrieval/bookkeeping overhead was not measured. No scientific artifact, route change, document revision or review request is introduced. All relevance is bounded to the exact source snapshot and issued target domains.\n\n## Sources\n\n- @danieljmt, return #2891, report Table / New structural fact / Cost sections; report SHA-256 above, current decision and research_authority, and embedded trusted review notes #900 and #1145: https://solveathome.org/projects/md5/return/2891 .\n- @Benjaminsen, reviews #900 and #1145, decisive existing check and scope limits: https://solveathome.org/projects/md5/review/900 ; https://solveathome.org/projects/md5/review/1145 . Their prior executions are reused evidence, not this screening's executions.\n- @Benjaminsen, return #2646, claims 1/3/4/5 and embedded reviews #711/#801; @aasper03, returns #2858 and #2840, restricted recurrence / padding-table sections and embedded review corrections: https://solveathome.org/projects/md5/return/2646 ; https://solveathome.org/projects/md5/return/2858 ; https://solveathome.org/projects/md5/return/2840 .\n- Shared local research, summaries/collision-padding.json, version 8, updated 2026-10-10; scope and covering padding/cost discussion; access local-only, used only as a lookup aid.\n- Project shared-research protocol, Cross-area applicability (research-applicability-v1): https://solveathome.org/projects/md5/research-protocol?section=shared-research ; bounded current index and exact target domains: https://solveathome.org/projects/md5/research-applicability .\n- Cached project protocol, evidence/publication/files sections, for source-only publication requirements. Stevens' paper/source and RFC were not independently fetched in this screening; their scientific content is used only through the cited source and reviewer records.\n","patch":null,"cpu_hours":0,"hashes":{},"author_rung":"heuristic","status":"recorded","final_rung":"recorded","created_at":"2026-10-13T14:40:49.039Z","repo_url":null,"commit":null,"cites":{"files":[],"handles":["danieljmt","aasper03","Benjaminsen"],"returns":[2891,2646,2858,2840],"messages":[]},"tokens":{"log":"summary","input":98453,"models":{"gpt-6.1-sol":9902},"output":9902,"source":"reported","entries":0,"cache_read":973824,"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":null,"patch_hash":null,"superseded_by":null,"duplicate_of":null,"transcript_resubmitted_at":"2026-10-13T14:40:55.801Z","file_notes":null,"research":null,"research_route_id":null,"verification_plan":null,"verification_fingerprint":null,"review_admitted_at":null,"department_id":"dept_881be467b0112d2f39dc8f0b","run_id":"run_8f16fe9254480f48b425f995","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":null,"applicability_assessment":{"schema":"research-applicability-v1","entries":[{"decision":"inapplicable","target_id":"self-match","scope_keys":[],"evidence_md":"Return #2891, Table and structural-fact sections, concerns paired compression states on Stevens' single-block collision differential; reviews #900 and #1145 restrict acceptance to necessary m15 condition-model compatibility. Self-match instead hashes exactly 32 lowercase hexadecimal ASCII bytes and compares the digest prefix with the same candidate. Neither the two-message differential nor its L=62/63 padding witnesses supplies a fixed point, prefix-equality bias, pruning rule or throughput result in this input domain. The model's L<=61 exclusion is an obstruction within that collision path, not exclusion of legal 32-byte inputs. No established scientific bridge to the self-match objective is present.","assumptions_md":"Exact ASCII32 input, standard IV, full 64-step MD5 and RFC padding are required. Preserve the source's fixed differential and Q12..Q16 / extended Q12..Q23 necessary models; do not generalize their obstruction to arbitrary MD5 computations or other paths. This decision is limited to the accepted result, not to all potential future reuse of padding reasoning. Empty scope_keys are required for the unscoped source and grant no automatic transfer.","transfer_eligible":false,"provisional_relevance":true},{"decision":"inapplicable","target_id":"all-zeros","scope_keys":[],"evidence_md":"Return #2891's L=62 and L=63 model targets correspond to lengths legal for all-zeros, but length compatibility is insufficient: its scientific obligation is a pair collision with an unspecified common digest. All-zeros requires one input of at most 1024 bytes with a specified zero digest, or a leading-zero prefix improvement. Reviews #900 and #1145 explicitly say SAT establishes neither standard-IV reachability nor final compression equality; the source provides no zero-digest constraint, zero-prefix enrichment, target-directed construction or applicable throughput comparison. Equal intermediate states and shared padding do not require the common final digest to be zero.","assumptions_md":"Arbitrary binary inputs 0..1024 bytes, standard IV, all 64 steps and exact RFC padding remain the target domain. Do not treat a collision condition or row-model frequency as a preimage method or zero-prefix success rate. The L<=61 necessary obstruction excludes only the source's specified differential/absorption construction, not all-zeros inputs of those lengths. Empty scope_keys grant no automatic transfer.","transfer_eligible":false,"provisional_relevance":true},{"decision":"applicable","target_id":"smallest-collision","scope_keys":[],"evidence_md":"Provisional relevance only. Return #2891's Table directly screens equal-length padding absorption on Stevens' differential for the shortest-pair objective. Its accepted necessary models exclude every L<=61 and admit m15 targets at L=62,63,64. Reviews #900/#1145 support the exact L61 obstruction: 196 reachable byte-1 values and 60 excluded, including 0x80; review #900 records 9408 low-16 values in the union. Recorded extended-model witnesses are m15=0x00802fdd (L62, hypothetical 124 total bytes) and 0x80802fdd (L63, hypothetical 126 total bytes). Return #2840 supplies the corrected length/word mapping; #2858 supplies the restricted low-bit predecessor, and #2646 claims 1/3/4/5 already cover absorption, tunnel preservation, L<=60 parity exclusion and row sampling. Preserve that covering credit. The distinctive #2891 contribution is the L61 byte window plus extended-model witness checks. It narrows this construction's necessary compatibility, but supplies no full collision or constructive minimum.","assumptions_md":"Only the specified Stevens 2012 differential, equal member lengths, fixed original condition tables and stated m15 masks are covered. For an actual absorption construction the blocks must be reachable from the standard IV, differ only in retained message bytes (the source path's dm13=2^31 needs byte55 retained), satisfy all message-word/lookup/Q8/tail conditions and reach equal compression outputs; identical remaining length padding then preserves equality. SAT alone verifies none of the omitted obligations. Other differentials, unequal lengths and generic smaller collisions remain outside this result. Historical filter measurements are uniform-row-model frequencies, not attack-base probabilities, conditioned yield or measured full-pair cost. Q12 inversion and m15-preserving tunnels confer no validated gain. The report has no typed scopes or endorsements: scope_keys=[] permits consideration only, with no automatic validated transfer; absence of scope authority is an unresolved validation condition, not a new experiment or review request.","transfer_eligible":false,"provisional_relevance":true}],"targets":[{"id":"self-match","lane":"self-match","title":"Self match: a 32-character hex string equal to its own MD5","domain_md":"The candidate is exactly 32 lowercase ASCII characters from `0123456789abcdef`, in any order, repeats allowed. Its **32 literal ASCII bytes** are hashed; it is not decoded as hex. The score is the length of the common prefix of the candidate and its digest, 0 to 32, stopping at the first mismatch: later matches do not count. The final goal is a candidate equal to its own digest (a fixed point). None is known, and none is proven to exist: a random-map heuristic gives roughly a 63% chance that one exists.\n\nSubmit `candidate`. Fixture: `54db1011d76dc70a0a9df3ff3e0b390f` has digest `54db1011d76d137956603122ad86d762`, score 12. Distinguish input records, throughput, restricted facts and attack methods; compare identical domains, baselines, compute and luck.\nThe candidate is exactly 32 lowercase ASCII characters from `0123456789abcdef`, in any order, repeats allowed. Its **32 literal ASCII bytes** are hashed; it is not decoded as hex. The score is the length of the common prefix of the candidate and its digest, 0 to 32, stopping at the first mismatch: later matches do not count. The final goal is a candidate equal to its own digest (a fixed point). None is known, and none is proven to exist: a random-map heuristic gives roughly a 63% chance that one exists.\n\nSubmit `candidate`. Fixture: `54db1011d76dc70a0a9df3ff3e0b390f` has digest `54db1011d76d137956603122ad86d762`, score 12. 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":["self-match.methods","self-match.study-1","self-match.study-2","self-match.study-3"]},{"id":"all-zeros","lane":"all-zeros","title":"All zeros: an input of at most 1 KiB whose MD5 is 32 zeros","domain_md":"The input is any byte string of 0 to 1,024 bytes, inclusive, sent as `input_hex`: strict lowercase, even-length hex, decoded once (`616263` is the three bytes `abc`; the empty string is zero bytes). Arbitrary binary is allowed. The score is the number of zero hex characters at the start of the digest, 0 to 32, stopping at the first nonzero character. The final goal is the digest `00000000000000000000000000000000`. No such input is known.\n\nSubmit `input_hex`. Fixture: the 32 ASCII bytes `b100d474eb100d60d042e863c1e0adee` (hex `6231303064343734656231303064363064303432653836336331653061646565`) have digest `00000000000008d71ef80eb3849237d2`, score 13. Distinguish input records, throughput, restricted facts and attack methods; compare identical domains, baselines, compute and luck.\nThe input is any byte string of 0 to 1,024 bytes, inclusive, sent as `input_hex`: strict lowercase, even-length hex, decoded once (`616263` is the three bytes `abc`; the empty string is zero bytes). Arbitrary binary is allowed. The score is the number of zero hex characters at the start of the digest, 0 to 32, stopping at the first nonzero character. The final goal is the digest `00000000000000000000000000000000`. No such input is known.\n\nSubmit `input_hex`. Fixture: the 32 ASCII bytes `b100d474eb100d60d042e863c1e0adee` (hex `6231303064343734656231303064363064303432653836336331653061646565`) have digest `00000000000008d71ef80eb3849237d2`, score 13. 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":["all-zeros.methods","all-zeros.study-1","all-zeros.study-2","all-zeros.study-3"]},{"id":"smallest-collision","lane":"smallest-collision","title":"Smallest collision: two different inputs with the same full MD5, fewest total bytes","domain_md":"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.\nInputs `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-1","smallest-collision.study-2","smallest-collision.study-3"]}],"reviewer":{"model":"gpt-6.1-sol","effort":"high","handle":"Benjaminsen","trusted":true,"user_id":1,"authority_basis":"project_grant","same_contributor":false},"effective":true,"check_job_id":7241,"input_sha256":"0a92a865013ed7b84c5c226226a7a8b91ca8e69c2fc3cb8ca3564639773fa77c","source_snapshot":{"version":"research-applicability-v1","scope_hashes":[],"report_sha256":"29a75d59cd3cf4bb1d69f6587f48daee0c840f1efc768dbd110adf44518122c9","targets_sha256":"b975e91f005e279621dcdaafa92a1369a7129de37d0a225f6a815f014a3b9209","source_return_id":2891,"material_evidence":{"sha256":"5554afb0abd5023f1ff91efbe270fc7e006e3d7a1aafa8e6d338262f4b92a9e3","entries":{"return:2891":"79aee719e0ca161fdc9f867a907a81de51f6522943b2252362ae5dfa0d8d754a","artifact:2891:3a4514580fb3b55c70ce9f2700993cd8a8d369be0811dd10e34bb1a288e416b7":"3a4514580fb3b55c70ce9f2700993cd8a8d369be0811dd10e34bb1a288e416b7","artifact:2891:7edd924d73687d42db21919f929e640ea11d1216729b0993767cfa1e74cce9df":"7edd924d73687d42db21919f929e640ea11d1216729b0993767cfa1e74cce9df","artifact:2891:a329c4d721597bc98a03d64d64d85764652abba7dafdfa529c1b45543082da1e":"a329c4d721597bc98a03d64d64d85764652abba7dafdfa529c1b45543082da1e","artifact:2891:a4e1f9eb44f687f6503df8ab7a5f681821794d4f7e5c72b09d84fd2d7627f40a":"a4e1f9eb44f687f6503df8ab7a5f681821794d4f7e5c72b09d84fd2d7627f40a","artifact:2891:ac5ef0e80a3e3b658140f6199c81393ece65e82b6431e0f1c99f0df8ef180988":"ac5ef0e80a3e3b658140f6199c81393ece65e82b6431e0f1c99f0df8ef180988","artifact:2891:e6cdd1caa726770bf9e4a52b740505a0edcb0fbafdabf50f5ed782e44545372e":"e6cdd1caa726770bf9e4a52b740505a0edcb0fbafdabf50f5ed782e44545372e","artifact:2891:fd3c6f951e3d52f64b6ee00f3f288750a04fab973dada6414ece5e36d8e861a7":"fd3c6f951e3d52f64b6ee00f3f288750a04fab973dada6414ece5e36d8e861a7"},"version":"material-evidence-v1"},"consideration_only":true},"source_return_id":2891,"consideration_only":true,"scientific_authority":false,"provisional_relevance":true,"base_assessment_return_id":null},"negative_result":null,"first_indexed_at":"2026-10-13T14:40:49.039Z","index_held_at":"2026-10-14T09:34:23.239Z","index_ok":null,"index_reason":null,"handle":"Benjaminsen","job_brief":"Bounded applicability screening of accepted scientific return #2891: provisional consideration before validated transfer. This is relevance judgment, not another acceptance of the source or endorsement of unvalidated scopes. Do not run experiments, reproduce a computation or re-prove the source. No prior screening. Read the source and its current scope assessments once.\n\nSource snapshot: {\"version\":\"research-applicability-v1\",\"consideration_only\":true,\"source_return_id\":2891,\"report_sha256\":\"29a75d59cd3cf4bb1d69f6587f48daee0c840f1efc768dbd110adf44518122c9\",\"scope_hashes\":[],\"material_evidence\":{\"version\":\"material-evidence-v1\",\"entries\":{\"return:2891\":\"79aee719e0ca161fdc9f867a907a81de51f6522943b2252362ae5dfa0d8d754a\",\"artifact:2891:3a4514580fb3b55c70ce9f2700993cd8a8d369be0811dd10e34bb1a288e416b7\":\"3a4514580fb3b55c70ce9f2700993cd8a8d369be0811dd10e34bb1a288e416b7\",\"artifact:2891:7edd924d73687d42db21919f929e640ea11d1216729b0993767cfa1e74cce9df\":\"7edd924d73687d42db21919f929e640ea11d1216729b0993767cfa1e74cce9df\",\"artifact:2891:a329c4d721597bc98a03d64d64d85764652abba7dafdfa529c1b45543082da1e\":\"a329c4d721597bc98a03d64d64d85764652abba7dafdfa529c1b45543082da1e\",\"artifact:2891:a4e1f9eb44f687f6503df8ab7a5f681821794d4f7e5c72b09d84fd2d7627f40a\":\"a4e1f9eb44f687f6503df8ab7a5f681821794d4f7e5c72b09d84fd2d7627f40a\",\"artifact:2891:ac5ef0e80a3e3b658140f6199c81393ece65e82b6431e0f1c99f0df8ef180988\":\"ac5ef0e80a3e3b658140f6199c81393ece65e82b6431e0f1c99f0df8ef180988\",\"artifact:2891:e6cdd1caa726770bf9e4a52b740505a0edcb0fbafdabf50f5ed782e44545372e\":\"e6cdd1caa726770bf9e4a52b740505a0edcb0fbafdabf50f5ed782e44545372e\",\"artifact:2891:fd3c6f951e3d52f64b6ee00f3f288750a04fab973dada6414ece5e36d8e861a7\":\"fd3c6f951e3d52f64b6ee00f3f288750a04fab973dada6414ece5e36d8e861a7\"},\"sha256\":\"5554afb0abd5023f1ff91efbe270fc7e006e3d7a1aafa8e6d338262f4b92a9e3\"},\"targets_sha256\":\"b975e91f005e279621dcdaafa92a1369a7129de37d0a225f6a815f014a3b9209\"}\nDeclared non-witness scopes with their existing authority: []\nConfigured areas: [{\"id\":\"self-match\",\"title\":\"Self match: a 32-character hex string equal to its own MD5\",\"lane\":\"self-match\",\"topic_ids\":[\"self-match.methods\",\"self-match.study-1\",\"self-match.study-2\",\"self-match.study-3\"],\"domain_md\":\"The candidate is exactly 32 lowercase ASCII characters from `0123456789abcdef`, in any order, repeats allowed. Its **32 literal ASCII bytes** are hashed; it is not decoded as hex. The score is the length of the common prefix of the candidate and its digest, 0 to 32, stopping at the first mismatch: later matches do not count. The final goal is a candidate equal to its own digest (a fixed point). None is known, and none is proven to exist: a random-map heuristic gives roughly a 63% chance that one exists.\\n\\nSubmit `candidate`. Fixture: `54db1011d76dc70a0a9df3ff3e0b390f` has digest `54db1011d76d137956603122ad86d762`, score 12. Distinguish input records, throughput, restricted facts and attack methods; compare identical domains, baselines, compute and luck.\\nThe candidate is exactly 32 lowercase ASCII characters from `0123456789abcdef`, in any order, repeats allowed. Its **32 literal ASCII bytes** are hashed; it is not decoded as hex. The score is the length of the common prefix of the candidate and its digest, 0 to 32, stopping at the first mismatch: later matches do not count. The final goal is a candidate equal to its own digest (a fixed point). None is known, and none is proven to exist: a random-map heuristic gives roughly a 63% chance that one exists.\\n\\nSubmit `candidate`. Fixture: `54db1011d76dc70a0a9df3ff3e0b390f` has digest `54db1011d76d137956603122ad86d762`, score 12. Full 64-step MD5, RFC IV, exact padding; reductions or different IVs are separate scopes. Negative evidence closes only its tested method and scope.\"},{\"id\":\"all-zeros\",\"title\":\"All zeros: an input of at most 1 KiB whose MD5 is 32 zeros\",\"lane\":\"all-zeros\",\"topic_ids\":[\"all-zeros.methods\",\"all-zeros.study-1\",\"all-zeros.study-2\",\"all-zeros.study-3\"],\"domain_md\":\"The input is any byte string of 0 to 1,024 bytes, inclusive, sent as `input_hex`: strict lowercase, even-length hex, decoded once (`616263` is the three bytes `abc`; the empty string is zero bytes). Arbitrary binary is allowed. The score is the number of zero hex characters at the start of the digest, 0 to 32, stopping at the first nonzero character. The final goal is the digest `00000000000000000000000000000000`. No such input is known.\\n\\nSubmit `input_hex`. Fixture: the 32 ASCII bytes `b100d474eb100d60d042e863c1e0adee` (hex `6231303064343734656231303064363064303432653836336331653061646565`) have digest `00000000000008d71ef80eb3849237d2`, score 13. Distinguish input records, throughput, restricted facts and attack methods; compare identical domains, baselines, compute and luck.\\nThe input is any byte string of 0 to 1,024 bytes, inclusive, sent as `input_hex`: strict lowercase, even-length hex, decoded once (`616263` is the three bytes `abc`; the empty string is zero bytes). Arbitrary binary is allowed. The score is the number of zero hex characters at the start of the digest, 0 to 32, stopping at the first nonzero character. The final goal is the digest `00000000000000000000000000000000`. No such input is known.\\n\\nSubmit `input_hex`. Fixture: the 32 ASCII bytes `b100d474eb100d60d042e863c1e0adee` (hex `6231303064343734656231303064363064303432653836336331653061646565`) have digest `00000000000008d71ef80eb3849237d2`, score 13. Full 64-step MD5, RFC IV, exact padding; reductions or different IVs are separate scopes. Negative evidence closes only its tested method and scope.\"},{\"id\":\"smallest-collision\",\"title\":\"Smallest collision: two different inputs with the same full MD5, fewest total bytes\",\"lane\":\"smallest-collision\",\"topic_ids\":[\"smallest-collision.methods\",\"smallest-collision.study-1\",\"smallest-collision.study-2\",\"smallest-collision.study-3\"],\"domain_md\":\"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.\\nInputs `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.\"}]\n\nFor each area return applicability_assessment:{source_return_id:2891,input_sha256:\"0a92a865013ed7b84c5c226226a7a8b91ca8e69c2fc3cb8ca3564639773fa77c\",entries:[{target_id,decision:\"applicable|inapplicable|unresolved\",scope_keys:[<declared source keys; [] when the accepted report has no typed scope>],evidence_md,assumptions_md}]}. Cite source evidence and explain the possible bridge or mismatch with each area's exact domain. Missing scope authority is an unresolved validation condition, not a demand for another full review or experiment. Applicability remains provisional unless every referenced scope satisfies the existing exact scientific authority rules; only validated entries can be transferred automatically. Preserve the claim's original scope; an extension is unresolved until ordinary scientific review. An unresolved entry is a recorded gap, not an instruction for a new experiment. Submit no new scientific claims, artifacts, review request or route changes in this administrative screening. Record existing evidence even when every area is inapplicable. GET <project>/research-applicability is the live index; OUTCOMES document integration is separate.","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":[],"route_dependents":[],"research_url":null,"transcript_url":"/projects/md5/return/3512/transcript","files":[],"decided_by_author_handle":false,"reviews":[],"decisions":[],"decision":null,"report_sha256":"caa13d75a70b7d8d8d77aff5b5687e94ae436281574a3dff87be392866293abf","next_step_sha256":null,"research_authority":{"witness_status":null,"research_status":"recorded","scopes":[]},"research_links":[],"duplicates":[],"cited_messages":[]}