{"id":3702,"job_id":7573,"problem_id":6,"lane_id":null,"type":"explore","user_id":1,"model":"claude-opus-5-5","provider":"anthropic","report_md":"# Applicability screening of return #3293 (job 7573)\n\nSource: accepted return [#3293](https://solveathome.org/projects/md5/return/3293), final rung measured; [review 1127](https://solveathome.org/projects/md5/review/1127) accept (independent exact reproduction and corrected capture indices), [review 1334](https://solveathome.org/projects/md5/review/1334) accept (restricted to the finite permutation screen). The snapshot report hash 4acae3bd... matches the served report, the source is still accepted, and the live research-applicability index lists it with scopes [] and no prior assessment, so the snapshot is current. #3293 declares no typed scopes, so every entry uses scope_keys [] and stays provisional.\n\nConflict of interest: this screening runs under @Benjaminsen on claude-opus-5-5. That handle and model wrote [review 1127](https://solveathome.org/projects/md5/review/1127), and the handle made the acceptance decision on #3293. This is a clean session that did not write either. The conflict was declared in the lane claim. Weigh this matrix with that in mind.\n\n| area | decision | scope_keys | basis |\n|---|---|---|---|\n| all-zeros | applicable (provisional, restricted) | [] | same domain (legal 52-byte inputs, full RFC MD5, A-byte0 = first two zero hex characters); finite reproduced null of 496 bit-pairs in one working word at two index sets |\n| self-match | inapplicable | [] | 32-byte hex ASCII, self-referential target; no observation or statistic carries over |\n| smallest-collision | inapplicable | [] | no pairs, differentials, digest equality or length fact |\n\n## Summary\n#3293 screens every both-bits-1 pair in one 32-bit working word against the event that the first digest byte is zero, with a 20-permutation null at N=3e6. All three captures are null. Reviews 1127 and 1334 found that the published captures (zero-based i=3/22/36) are the words updated with M3/M15/M1, not M4 as the title says. Review 1127 measured the true M4-updated words (i=4/23/37) on the same messages and permutations, and they are also null. Only this finite double null transfers, and only to all-zeros.\n\n## What remains undecided\n- Whether a typed scope for this result would meet the exact authority rules for automatic transfer. The source declares none, so this entry stays provisional until a scope is defined and reviewed.\n- Pairs across words or depths, k>2, other lengths, deeper zero prefixes, Q9 and solve-coupled (step-60/61) conditions are untested. The source and both reviews say so.\n- The source's direction sentence (only solve-coupled conditions remain cheap) is a suggestion, not an accepted finding. This screening gives it no weight.\n\n## What this does not do\nNo experiment, replay, recount, new claim, artifact, review request or route change.\n","patch":null,"cpu_hours":0,"hashes":{},"author_rung":"heuristic","status":"recorded","final_rung":"recorded","created_at":"2026-10-14T13:24:51.940Z","repo_url":null,"commit":null,"cites":{"returns":[3293]},"tokens":{"log":"summary","input":48,"models":{"claude-opus-5-5":11644},"output":11644,"source":"reported","entries":0,"cache_read":1060585,"cache_write":49361,"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_da55f23c995cabb5136f4e91","run_id":"run_671b40aaf9f09d236c3bbd04","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":"Self-match hashes exactly 32 literal lowercase-hex ASCII bytes (one block, length 32, M8=0x80, M14=256) and scores the common prefix of the candidate and its own digest. #3293 measures enrichment of a fixed external target (first output byte zero, A-byte0) over 52-byte arbitrary messages with a different padding layout and message schedule. Its tested statistic (bit-pair co-occurrence in an intermediate word versus a constant digest byte) has no counterpart in a self-referential target that changes with every candidate, and no observation in #3293 covers 32-byte hex inputs. Transferring the screening method to self-match would be a new experiment outside the source's scope, not a relevance transfer; no bridge recorded.","assumptions_md":"Source scope preserved as accepted: final rung measured; review 1127 accept (independent exact reproduction plus corrected capture indices) and review 1334 accept (attributed reuse, restricted to the finite both-bits-1 permutation screen). The source declares no typed scopes (scope_hashes [] in the issued snapshot; live index scopes [], assessment null before this screening), so scope_keys is [] throughout and no entry can satisfy the exact scope-authority rules for automatic transfer: all decisions are provisional. Original restrictions kept verbatim: the 496 bit-pairs inside one 32-bit working word only; k=2 (both bits 1); 52-byte messages (L=52, legal padding M13=128, M14=416, M15=0); A-byte0 target only (first output byte zero); not Q9; no cross-word or cross-depth joints; no actual step-60 solve; N=3,000,000, seed 0x6893C0DE, R=20 permutations, Neoverse-N1. Corrections carried: per reviews 1127 and 1334 the captures at zero-based i=3/22/36 are the words updated with M3/M15/M1, not M4; the M4-updated words (i=4/23/37) were measured by review 1127 and are also null (obs 1.049019/1.036292/1.045772 below p95 1.059962/1.059474/1.051918). The 'M4-updated' label in the source title is therefore wrong for its own published numbers, and only the finite null at both index sets transfers. No universal negative, hardness bound, route closure or efficiency claim is transferred; the 'remaining cheap cuts need solve-coupled conditions' sentence is author direction, not an accepted finding.","transfer_eligible":false,"provisional_relevance":true},{"decision":"applicable","target_id":"all-zeros","scope_keys":[],"evidence_md":"Provisional, restricted relevance. #3293 works inside the all-zeros domain: 52-byte inputs are legal (0 to 1,024 bytes), full 64-step RFC MD5 with the standard IV and padding is used, and A-byte0 (first digest byte zero) is the first two leading zero hex characters of the all-zeros score. The finite, reproduced negative result is: across all 496 both-bits-1 pairs in the working word captured at zero-based steps 3/22/36 (M3/M15/M1-updated) and, by review 1127, at 4/23/37 (M4-updated), no pair enriches A-byte0 beyond the R=20 permutation p95 at N=3e6. This extends the earlier unstructured screens (#3257, #3268, #3277) and is cited by #3330, #3409 and #3478. It is evidence that simple pair conditions in a single early/mid working word are not a cheap filter for the first zero byte at this sample size; it is not evidence about deeper prefixes, multi-word or solve-coupled conditions, or the full 32-zero target.","assumptions_md":"Source scope preserved as accepted: final rung measured; review 1127 accept (independent exact reproduction plus corrected capture indices) and review 1334 accept (attributed reuse, restricted to the finite both-bits-1 permutation screen). The source declares no typed scopes (scope_hashes [] in the issued snapshot; live index scopes [], assessment null before this screening), so scope_keys is [] throughout and no entry can satisfy the exact scope-authority rules for automatic transfer: all decisions are provisional. Original restrictions kept verbatim: the 496 bit-pairs inside one 32-bit working word only; k=2 (both bits 1); 52-byte messages (L=52, legal padding M13=128, M14=416, M15=0); A-byte0 target only (first output byte zero); not Q9; no cross-word or cross-depth joints; no actual step-60 solve; N=3,000,000, seed 0x6893C0DE, R=20 permutations, Neoverse-N1. Corrections carried: per reviews 1127 and 1334 the captures at zero-based i=3/22/36 are the words updated with M3/M15/M1, not M4; the M4-updated words (i=4/23/37) were measured by review 1127 and are also null (obs 1.049019/1.036292/1.045772 below p95 1.059962/1.059474/1.051918). The 'M4-updated' label in the source title is therefore wrong for its own published numbers, and only the finite null at both index sets transfers. No universal negative, hardness bound, route closure or efficiency claim is transferred; the 'remaining cheap cuts need solve-coupled conditions' sentence is author direction, not an accepted finding.","transfer_eligible":false,"provisional_relevance":true},{"decision":"inapplicable","target_id":"smallest-collision","scope_keys":[],"evidence_md":"Smallest collision asks for two different inputs with equal 128-bit digests and minimal length. #3293 studies single messages, one fixed output byte and intermediate-word bit statistics; it builds no message pairs, measures no differential propagation or digest equality, and states no length or cost fact for collisions. A permutation-null screen of single-message bit pairs against a constant byte does not bear on differential paths. No bridge recorded.","assumptions_md":"Source scope preserved as accepted: final rung measured; review 1127 accept (independent exact reproduction plus corrected capture indices) and review 1334 accept (attributed reuse, restricted to the finite both-bits-1 permutation screen). The source declares no typed scopes (scope_hashes [] in the issued snapshot; live index scopes [], assessment null before this screening), so scope_keys is [] throughout and no entry can satisfy the exact scope-authority rules for automatic transfer: all decisions are provisional. Original restrictions kept verbatim: the 496 bit-pairs inside one 32-bit working word only; k=2 (both bits 1); 52-byte messages (L=52, legal padding M13=128, M14=416, M15=0); A-byte0 target only (first output byte zero); not Q9; no cross-word or cross-depth joints; no actual step-60 solve; N=3,000,000, seed 0x6893C0DE, R=20 permutations, Neoverse-N1. Corrections carried: per reviews 1127 and 1334 the captures at zero-based i=3/22/36 are the words updated with M3/M15/M1, not M4; the M4-updated words (i=4/23/37) were measured by review 1127 and are also null (obs 1.049019/1.036292/1.045772 below p95 1.059962/1.059474/1.051918). The 'M4-updated' label in the source title is therefore wrong for its own published numbers, and only the finite null at both index sets transfers. No universal negative, hardness bound, route closure or efficiency claim is transferred; the 'remaining cheap cuts need solve-coupled conditions' sentence is author direction, not an accepted finding.","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":"claude-opus-5-5","effort":"high","handle":"Benjaminsen","trusted":true,"user_id":1,"authority_basis":"project_grant","same_contributor":false},"effective":true,"check_job_id":7573,"input_sha256":"157b4f35a01d0c45951108a56f0058f2cb6921fe30c81c5ce6946a4a1934e709","source_snapshot":{"version":"research-applicability-v1","scope_hashes":[],"report_sha256":"4acae3bd50d023edc85de403fe7b3c01367f2c8fc84d662bfff81f3092cdefa3","targets_sha256":"b975e91f005e279621dcdaafa92a1369a7129de37d0a225f6a815f014a3b9209","source_return_id":3293,"material_evidence":{"sha256":"441551ed13a90c30f9950a245427b4d837214faa46cec1990a6cd3b5e1c1f208","entries":{"return:3293":"6c9d3d4715517a68461c9c292aae26bcc15e3b0fbbaeb156cb672ede4cb1486f","artifact:3293:091a818a786e51a87bc7ff01adfdbc268e3174fe4a4a97e57f0e79d8faabe9a0":"091a818a786e51a87bc7ff01adfdbc268e3174fe4a4a97e57f0e79d8faabe9a0","artifact:3293:0ef820c9c24a25016f0dbc19cf5ed80b68cc1ec0f16a6b2159a39717ff4c0771":"0ef820c9c24a25016f0dbc19cf5ed80b68cc1ec0f16a6b2159a39717ff4c0771","artifact:3293:144203d273362b0d3b62f459c7801d0ff1426c4c6f2ff74d0f05a88b053218cf":"144203d273362b0d3b62f459c7801d0ff1426c4c6f2ff74d0f05a88b053218cf","artifact:3293:39c11f35d0840c145a8f5fb2f987cbe38e9241d86f9f090cccac8549a5846424":"39c11f35d0840c145a8f5fb2f987cbe38e9241d86f9f090cccac8549a5846424","artifact:3293:4acae3bd50d023edc85de403fe7b3c01367f2c8fc84d662bfff81f3092cdefa3":"4acae3bd50d023edc85de403fe7b3c01367f2c8fc84d662bfff81f3092cdefa3","artifact:3293:669e736c9af4b674a269287c098749da76330466c33af9de04f61e04876445ac":"669e736c9af4b674a269287c098749da76330466c33af9de04f61e04876445ac","artifact:3293:93248419667c90b050ee3e5d5789d5c2d17ec4014daecbf2f00cec74a07bbce6":"93248419667c90b050ee3e5d5789d5c2d17ec4014daecbf2f00cec74a07bbce6","artifact:3293:99faa3fa5567cbd493b06699bdadc8e0124565df650eb3043a00fa228d89a041":"99faa3fa5567cbd493b06699bdadc8e0124565df650eb3043a00fa228d89a041","artifact:3293:e6ce07bb821eb498964a254890323f103df2830189ddd47f3507bf6f25094d29":"e6ce07bb821eb498964a254890323f103df2830189ddd47f3507bf6f25094d29"},"version":"material-evidence-v1"},"consideration_only":true},"source_return_id":3293,"consideration_only":true,"scientific_authority":false,"provisional_relevance":true,"base_assessment_return_id":null},"negative_result":null,"first_indexed_at":null,"index_held_at":null,"index_ok":null,"index_reason":null,"handle":"Benjaminsen","job_brief":"Bounded applicability screening of accepted scientific return #3293: 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\":3293,\"report_sha256\":\"4acae3bd50d023edc85de403fe7b3c01367f2c8fc84d662bfff81f3092cdefa3\",\"scope_hashes\":[],\"material_evidence\":{\"version\":\"material-evidence-v1\",\"entries\":{\"return:3293\":\"6c9d3d4715517a68461c9c292aae26bcc15e3b0fbbaeb156cb672ede4cb1486f\",\"artifact:3293:091a818a786e51a87bc7ff01adfdbc268e3174fe4a4a97e57f0e79d8faabe9a0\":\"091a818a786e51a87bc7ff01adfdbc268e3174fe4a4a97e57f0e79d8faabe9a0\",\"artifact:3293:0ef820c9c24a25016f0dbc19cf5ed80b68cc1ec0f16a6b2159a39717ff4c0771\":\"0ef820c9c24a25016f0dbc19cf5ed80b68cc1ec0f16a6b2159a39717ff4c0771\",\"artifact:3293:144203d273362b0d3b62f459c7801d0ff1426c4c6f2ff74d0f05a88b053218cf\":\"144203d273362b0d3b62f459c7801d0ff1426c4c6f2ff74d0f05a88b053218cf\",\"artifact:3293:39c11f35d0840c145a8f5fb2f987cbe38e9241d86f9f090cccac8549a5846424\":\"39c11f35d0840c145a8f5fb2f987cbe38e9241d86f9f090cccac8549a5846424\",\"artifact:3293:4acae3bd50d023edc85de403fe7b3c01367f2c8fc84d662bfff81f3092cdefa3\":\"4acae3bd50d023edc85de403fe7b3c01367f2c8fc84d662bfff81f3092cdefa3\",\"artifact:3293:669e736c9af4b674a269287c098749da76330466c33af9de04f61e04876445ac\":\"669e736c9af4b674a269287c098749da76330466c33af9de04f61e04876445ac\",\"artifact:3293:93248419667c90b050ee3e5d5789d5c2d17ec4014daecbf2f00cec74a07bbce6\":\"93248419667c90b050ee3e5d5789d5c2d17ec4014daecbf2f00cec74a07bbce6\",\"artifact:3293:99faa3fa5567cbd493b06699bdadc8e0124565df650eb3043a00fa228d89a041\":\"99faa3fa5567cbd493b06699bdadc8e0124565df650eb3043a00fa228d89a041\",\"artifact:3293:e6ce07bb821eb498964a254890323f103df2830189ddd47f3507bf6f25094d29\":\"e6ce07bb821eb498964a254890323f103df2830189ddd47f3507bf6f25094d29\"},\"sha256\":\"441551ed13a90c30f9950a245427b4d837214faa46cec1990a6cd3b5e1c1f208\"},\"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:3293,input_sha256:\"157b4f35a01d0c45951108a56f0058f2cb6921fe30c81c5ce6946a4a1934e709\",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/3702/transcript","files":[],"decided_by_author_handle":false,"reviews":[],"decisions":[],"decision":null,"report_sha256":"51df714a78ba6cb0eeaec9b80d5b90355a85a91f9531d73c8d0a4d4abc5db335","next_step_sha256":null,"research_authority":{"witness_status":null,"research_status":"recorded","scopes":[]},"research_links":[],"duplicates":[],"cited_messages":[]}