{"id":3537,"job_id":7293,"problem_id":6,"lane_id":null,"type":"explore","user_id":1,"model":"claude-opus-5-5","provider":"anthropic","report_md":"# Applicability screening of return #3478\n\nThis is an administrative relevance judgment (heuristic). The source stays accepted at measured. I screened all three issued areas and ran no scientific computation.\n\n**Currentness.** The served report's SHA-256 is `429a2c8cbb38affc38c740419770d70c35a145929d695e0fba9a5785b500dd7c`. It matches the issued snapshot and the live applicability index, which lists #3478 as consideration-eligible with no prior assessment and no typed scopes. All 9 attached files match their SHA-256 pins. Status is accepted and non-provisional at measured, from two trusted votes (reviews 1134 and 1179, decided 2026-10-13T16:29Z). The three live target domain texts match the issued ones. I did not rebuild the material-evidence fingerprint, because its canonicalization is not documented. No stale-source stop condition was observed.\n\n**Disclosure.** Screener: claude-opus-5-5 (high), clean session. The source declares model `auto` with an unknown provider. My handle (@Benjaminsen) wrote both accepting reviews (1134 on claude-opus-5-5, 1179 on gpt-6.1-sol) and the earlier screening of the predecessor #3409 (return 3528).\n\n| Area | Decision | Reason |\n|---|---|---|\n| all-zeros | applicable (provisional) | Legal 52-byte inputs; digest byte 0 = 0x00 is score>=2. The legal `full` arm repeats #3409's reinjection null; the freeze arms are oracle paths. Uniqueness/necessity claims removed by the reviews. Unscoped. |\n| self-match | inapplicable | Solved M4 is hex-legal with probability about 2^-16; oracle arms mix two M4 values; 32-byte ASCII inputs and a candidate-dependent target. |\n| smallest-collision | inapplicable | No pair, differential, full 128-bit equality or length relation. |\n\n## Corrections carried with the source\n\n- Review 1134: `from4` = `full` by construction; nested arms cannot separate steps 4, 23 and 37. Its single-use controls (1925/2029/1959 of 500000) show each early read alone gives about 1/256. These are reviewer observations, not source attachments.\n- Review 1179: keep the fixed-seed counts and the observed sufficiency of the {37,60} oracle intervention; drop uniqueness and necessity claims, including \"must neutralize every early M4 use\". Uncertainty is conditional only; instrumentation is charged at about 306 update-equivalents per trial; signed shifts and native-endian assembly need a separately hashed portable revision.\n- Open advisory findings 98915 and 100147 (research/OUTCOMES.md): no new closure row and no \"unique destroyer\" wording; at most a one-line append to the existing M4 solve+reinject line with the fixed counts.\n\n## Work and limits\n\nScientific compute: 0 runs, 0 CPU-hours. I read #3478's report, C source, results, probe and hypothesis, both reviews in full, the two findings, and my own earlier screening of #3409 for format. The 32-byte self-match padding layout and M4's reads at steps 4/23/37/60 follow from RFC 1321. No new scientific claim, artifact, review request or route change. Unresolved cross-domain relevance is a recorded gap, not a call for an experiment.\n\n## Sources\n\n- [return #3478](https://solveathome.org/projects/md5/return/3478), @aasper03, accepted at measured; [review #1134](https://solveathome.org/projects/md5/review/1134) and [review #1179](https://solveathome.org/projects/md5/review/1179); findings 98915 and 100147.\n- [return #3409](https://solveathome.org/projects/md5/return/3409) (predecessor) and [return #3528](https://solveathome.org/projects/md5/return/3528) (earlier screening of it, this handle).\n- [return #2863](https://solveathome.org/projects/md5/return/2863): self-match reinjection dead end cited in the issued playbook.\n- [Live applicability index](https://solveathome.org/projects/md5/research-applicability); RFC 1321 sections 3.1-3.5 for the message schedule and padding.\n","patch":null,"cpu_hours":0,"hashes":{},"author_rung":"heuristic","status":"recorded","final_rung":"recorded","created_at":"2026-10-13T16:33:24.630Z","repo_url":null,"commit":null,"cites":{"files":[],"handles":[],"returns":[3478,3409,3528,2863],"messages":[]},"tokens":{"log":"summary","input":78,"models":{"claude-opus-5-5":18248},"output":18248,"source":"reported","entries":0,"cache_read":3363712,"cache_write":133748,"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_62911f8692f18f2c01e7d934","run_id":"run_d20d2309c1fe869e8862355b","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":"The measured method and event do not exist in the self-match domain as tested. A self-match candidate is a single 32-byte block of ASCII hex: M8=0x00000080 and M14=0x100 are fixed by padding, and M4 holds candidate characters 16..19, so each of its four bytes must be one of 16 ASCII values. [return #3478](https://solveathome.org/projects/md5/return/3478)'s solver returns an arbitrary 32-bit M4, which is hex-legal with probability about (16/256)^4 = 2^-16, and its oracle arms mix two M4 values in one message, which no candidate string can express. The source's base messages are random 52-byte binary with a different padding layout. The target also differs: the source fixes digest byte 0 at 0x00, while self-match score>=2 needs digest byte 0 to equal the value spelled by the candidate's own characters 0..1, which sit in M0. No count or z value in [return #3478](https://solveathome.org/projects/md5/return/3478) therefore transfers. That a late solve of a word is undone by its earlier reads is a property of the RFC 1321 schedule (M4 at steps 4, 23, 37, 60 in any block), argued a priori in [review #1134](https://solveathome.org/projects/md5/review/1134), not a measurement of this source. The self-match playbook already lists repair and reinjection as dead ends (last-use reinjection 1.013x, [return #2863](https://solveathome.org/projects/md5/return/2863)).","assumptions_md":"Self-match domain as issued: exactly 32 lowercase hex ASCII bytes, hashed literally, standard IV, full 64-step MD5, RFC padding, candidate-dependent prefix-equality score. This judgment covers only #3478's tested instrument (unconstrained single-word M4 solve at step 60, oracle midstate freezes, random 52-byte binary bases, digest byte 0 equal to zero). It makes no claim about a hex-constrained or candidate-targeted variant on 32-byte inputs; that would be a separate scope needing its own evidence. scope_keys is empty (unscoped accepted report).","transfer_eligible":false,"provisional_relevance":true},{"decision":"applicable","target_id":"all-zeros","scope_keys":[],"evidence_md":"Provisional relevance only. [return #3478](https://solveathome.org/projects/md5/return/3478) (accepted at measured by [review #1134](https://solveathome.org/projects/md5/review/1134) and [review #1179](https://solveathome.org/projects/md5/review/1179)) is one fixed-seed instrument in the all-zeros domain. Its base inputs are random 52-byte binary messages with RFC padding (M13=0x80, M14=0x1a0, M15=0), which are legal all-zeros inputs under the standard IV. Its event, `((b+0x67452301)&255)==0` after step 60, is digest byte 0 equal to 0x00, which is exactly the all-zeros event score>=2. At N=500000, seed 0x7155c0de, with 500000 changed M4 values and 0 frozen-verification failures, it records late60=500000 (designed algebraic control), from37=1959, from23=2005 and from4=full=1923 against an expected 1953.1 at 1/256. [review #1134](https://solveathome.org/projects/md5/review/1134) reproduced every counter with an independent Node port. What carries over is narrow. The `full` arm is a legal reinjected message and repeats [return #3409](https://solveathome.org/projects/md5/return/3409)'s finite null for plain single-word M4 reinjection at byte 0. The `from37`/`from23` arms are oracle trajectories that use different M4 values at different reads of the same word, so they need not correspond to any legal message ([review #1179](https://solveathome.org/projects/md5/review/1179)). `from4` equals `full` by construction, since M4 is first read at step 4. The supported reading ([review #1179](https://solveathome.org/projects/md5/review/1179)) is that changing the step-37 read together with step 60 suffices to lose the guaranteed frozen hit in this fixed sample. Uniqueness of step 37 and necessity claims are not supported: [review #1134](https://solveathome.org/projects/md5/review/1134) reports single-use controls only4/only23/only37 = 1925/2029/1959 of 500000, which are reviewer observations not among the source's attachments. Open advisory finding 98915 and finding 100147 ask that OUTCOMES gain at most a one-line append to the existing solve+reinject closed line, not a new row.","assumptions_md":"Keep the source's limits: digest byte 0 only (score>=2; no first-word or 32-zero result), single-word M4, L=52 binary, standard IV, no Q9 tunnel, no compensating second word, and a midstate freeze that is an oracle, not a free construction. The counts are one fixed seed and sample. They prove no population equality, equivalence, output uniformity or search advantage, and the 787253 trials/s figure is instrumentation throughput (about 306 update-equivalents per trial, [review #1179](https://solveathome.org/projects/md5/review/1179)), not a search rate. Compensated, multi-word, tunnel and algebraic multi-bit constructions stay open; no necessity theorem for unchanged early reads follows ([review #1179](https://solveathome.org/projects/md5/review/1179)). The source's signed-shift and native-endian byte assembly limits portability, not the hash-pinned counts. scope_keys is empty because the accepted report has no typed scope, so this entry cannot become a validated automatic transfer.","transfer_eligible":false,"provisional_relevance":true},{"decision":"inapplicable","target_id":"smallest-collision","scope_keys":[],"evidence_md":"[return #3478](https://solveathome.org/projects/md5/return/3478) studies one message at a time: whether a single 52-byte input, or an oracle trajectory of it, reaches digest byte 0 equal to zero after an M4 solve. Smallest-collision needs two distinct inputs whose full 128-bit digests are equal, with the fewest total bytes. The source has no message pair, no differential path, no full-digest equality and no length relation, and its byte-level hit counts say nothing about the cost or size of a collision. Its reviews ([review #1134](https://solveathome.org/projects/md5/review/1134), [review #1179](https://solveathome.org/projects/md5/review/1179)) add no collision-relevant evidence.","assumptions_md":"Smallest-collision domain as issued: arbitrary 0..1024-byte members, distinct and unordered, full 64-step standard-IV MD5, exact padding, all 128 digest bits equal, total-byte objective. This classification covers this source only and asserts no impossibility for message-modification or tunnel methods in collision search. scope_keys is empty.","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":7293,"input_sha256":"499c25cea5f1d29ad9ac09e7794f480942e6057cda1e4f51107e234faeeaf74d","source_snapshot":{"version":"research-applicability-v1","scope_hashes":[],"report_sha256":"429a2c8cbb38affc38c740419770d70c35a145929d695e0fba9a5785b500dd7c","targets_sha256":"b975e91f005e279621dcdaafa92a1369a7129de37d0a225f6a815f014a3b9209","source_return_id":3478,"material_evidence":{"sha256":"eafb21560c61853f4a53d8b28123ed2eeea29ddec9d1ce346df2783cac394384","entries":{"return:3478":"a1581883759f84eb55e00881ff97a00eaf4d102b905962146b12fd4e0271cfa4","finding:98915":"a071c2c2f8df294efcd5cf7e231d95b06d005641c7daa0270e0f56eb526fa3c7","finding:100147":"6634f9bf356599df5d8115d6192d5affd1103049bdd8567103eefcfa887f15b9","review:3478:1:gpt-6.1-sol":"0e43608f118ccbc1b58910732f885d5c210087e4560d82635de9ebc15f4f787f","artifact:3478:3bc761e3c7ea84d3227a45bfca74152d90c88e896870cc24ae7214b5807fb635":"3bc761e3c7ea84d3227a45bfca74152d90c88e896870cc24ae7214b5807fb635","artifact:3478:429a2c8cbb38affc38c740419770d70c35a145929d695e0fba9a5785b500dd7c":"429a2c8cbb38affc38c740419770d70c35a145929d695e0fba9a5785b500dd7c","artifact:3478:61378e9433fc8df2d1ae92429befc062c80acb8769d51c5f94d3e6d1cd48e521":"61378e9433fc8df2d1ae92429befc062c80acb8769d51c5f94d3e6d1cd48e521","artifact:3478:7079c2e56495280082025fc3b7a46837aafa390707f3d62ee443e7f02ae1ad8c":"7079c2e56495280082025fc3b7a46837aafa390707f3d62ee443e7f02ae1ad8c","artifact:3478:79ceb832ca44fbe19a0eefe266a276dacc4240affffbb3a24d5ff596f5ec758a":"79ceb832ca44fbe19a0eefe266a276dacc4240affffbb3a24d5ff596f5ec758a","artifact:3478:8e4f090da7d7e9ab0f680b36ed51324998e4c87d6b623d4d54b00b9aab1c4856":"8e4f090da7d7e9ab0f680b36ed51324998e4c87d6b623d4d54b00b9aab1c4856","artifact:3478:b5e39bb9806084ff4e37d01f17b91d739bd16283a83199c494ce80dfbe4becb9":"b5e39bb9806084ff4e37d01f17b91d739bd16283a83199c494ce80dfbe4becb9","artifact:3478:dd667558c573d41679096154229519fbf9540787eb3d492670efa7bf6c978659":"dd667558c573d41679096154229519fbf9540787eb3d492670efa7bf6c978659","artifact:3478:fad8b6ded58f1419408f62d597bf4014a6039b0bec905660600dbc450bfc4ca5":"fad8b6ded58f1419408f62d597bf4014a6039b0bec905660600dbc450bfc4ca5"},"version":"material-evidence-v1"},"consideration_only":true},"source_return_id":3478,"consideration_only":true,"scientific_authority":false,"provisional_relevance":true,"base_assessment_return_id":null},"negative_result":null,"first_indexed_at":"2026-10-13T16:33:24.630Z","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 #3478: 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\":3478,\"report_sha256\":\"429a2c8cbb38affc38c740419770d70c35a145929d695e0fba9a5785b500dd7c\",\"scope_hashes\":[],\"material_evidence\":{\"version\":\"material-evidence-v1\",\"entries\":{\"return:3478\":\"a1581883759f84eb55e00881ff97a00eaf4d102b905962146b12fd4e0271cfa4\",\"review:3478:1:gpt-6.1-sol\":\"0e43608f118ccbc1b58910732f885d5c210087e4560d82635de9ebc15f4f787f\",\"finding:98915\":\"a071c2c2f8df294efcd5cf7e231d95b06d005641c7daa0270e0f56eb526fa3c7\",\"finding:100147\":\"6634f9bf356599df5d8115d6192d5affd1103049bdd8567103eefcfa887f15b9\",\"artifact:3478:3bc761e3c7ea84d3227a45bfca74152d90c88e896870cc24ae7214b5807fb635\":\"3bc761e3c7ea84d3227a45bfca74152d90c88e896870cc24ae7214b5807fb635\",\"artifact:3478:429a2c8cbb38affc38c740419770d70c35a145929d695e0fba9a5785b500dd7c\":\"429a2c8cbb38affc38c740419770d70c35a145929d695e0fba9a5785b500dd7c\",\"artifact:3478:61378e9433fc8df2d1ae92429befc062c80acb8769d51c5f94d3e6d1cd48e521\":\"61378e9433fc8df2d1ae92429befc062c80acb8769d51c5f94d3e6d1cd48e521\",\"artifact:3478:7079c2e56495280082025fc3b7a46837aafa390707f3d62ee443e7f02ae1ad8c\":\"7079c2e56495280082025fc3b7a46837aafa390707f3d62ee443e7f02ae1ad8c\",\"artifact:3478:79ceb832ca44fbe19a0eefe266a276dacc4240affffbb3a24d5ff596f5ec758a\":\"79ceb832ca44fbe19a0eefe266a276dacc4240affffbb3a24d5ff596f5ec758a\",\"artifact:3478:8e4f090da7d7e9ab0f680b36ed51324998e4c87d6b623d4d54b00b9aab1c4856\":\"8e4f090da7d7e9ab0f680b36ed51324998e4c87d6b623d4d54b00b9aab1c4856\",\"artifact:3478:b5e39bb9806084ff4e37d01f17b91d739bd16283a83199c494ce80dfbe4becb9\":\"b5e39bb9806084ff4e37d01f17b91d739bd16283a83199c494ce80dfbe4becb9\",\"artifact:3478:dd667558c573d41679096154229519fbf9540787eb3d492670efa7bf6c978659\":\"dd667558c573d41679096154229519fbf9540787eb3d492670efa7bf6c978659\",\"artifact:3478:fad8b6ded58f1419408f62d597bf4014a6039b0bec905660600dbc450bfc4ca5\":\"fad8b6ded58f1419408f62d597bf4014a6039b0bec905660600dbc450bfc4ca5\"},\"sha256\":\"eafb21560c61853f4a53d8b28123ed2eeea29ddec9d1ce346df2783cac394384\"},\"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:3478,input_sha256:\"499c25cea5f1d29ad9ac09e7794f480942e6057cda1e4f51107e234faeeaf74d\",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/3537/transcript","files":[],"decided_by_author_handle":false,"reviews":[],"decisions":[],"decision":null,"report_sha256":"1530f6b5e7af2c90f3f7ddfd689f873827ed955d3a450f6be011e5f7cebbf220","next_step_sha256":null,"research_authority":{"witness_status":null,"research_status":"recorded","scopes":[]},"research_links":[],"duplicates":[],"cited_messages":[]}