Folds dav1d's 1904-line review verdict into the ticket as §0 (new),
preserves §§1-8 as the design log of the original Anchor6 proposal
that was reviewed. Status flips from "open · awaiting dav1d review"
to "open · dav1d GO with rewrite · spec revision pending before any
kernel ships."
Verdict matrix:
✅ GO: generic AnchorN substrate primitive (not fixed Anchor6)
✅ GO: Joseph6 as the first registered default grammar (not THE
ontology)
✅ GO: deterministic object-state canonicalization
✅ GO: axiom/physics-loaded WorldDimensionGrammar as the scalable
path
❌ NO-GO: hard-coding H₁..H₆ as final ontology
❌ NO-GO: runtime LLM-decided dimensionality (axioms MAY propose,
only deterministic validators may accept; grammars must
freeze via grammar_hash before proof-path use)
❌ NO-GO: framing this as a "semantic verifier warrant"
❌ NO-GO: relation/event/place/agent_trace in this ticket
❌ NO-GO: SQL persistence at Phase 1
Critical technical corrections:
- H₁ MUST use uint256, not uint64 (octree position entropy at
depth >8)
- Rotation mapper is map_rotation_euler_ypr(), NOT "SO(3)"
(review §17 — quantized Euler triple, no continuous SO(3))
- Canonical record carries grammar_hash + axiom_pack_hash +
manifest_hash + seed_hash alongside the per-dimension values
- Missing privacy.class = HARD reject (no PUBLIC fallback)
- spatial-anchor-object@v1 folds into canonicalization_version
only — no new audit_mode token, no verifier_policy_hash bump
Corrected package layout:
arborist/substrate/spatial_anchor.py (AnchorN, split_anchor_n)
arborist/world/grammar.py NEW — WorldDimensionGrammar
arborist/world/pi_star/object.py (derive_world_object_record
+ 5 mappers)
arborist/pi_star/spatial_anchor_object.py NEW — registry adapter
bench/fixtures/spatial-anchor-object/known-answer-tests.jsonl
tests/test_spatial_anchor.py
tests/test_world_dimension_grammar.py
tests/test_pi_star_spatial_anchor_object.py
Implementation NOT started — arborist/world/__init__.py STATUS still
"namespace_reserved"; only bench/spatial_anchor_validation.py
(pre-review empirical bench, commit 55b651f) on disk. Review arrives
at the right moment: no production code committed against the original
Anchor6 spec yet, so the AnchorN reframe lands in the spec before
the wrong primitive ships.
Full review archived at:
docs/dav1d-reviews/000070-spatial-anchor-pi-w-object--2026-06-01.txt
Five of ten original open questions resolved by the pre-review bench
(Q1/Q2/Q3/Q8/Q9); review answers Q4/Q5/Q6/Q7; Q10 (paper-amendment
wording) is the only remaining open question — substrate paper text
needs revision to introduce AnchorN + grammar layer instead of fixed
Anchor6.
russell@unturf.com
862662b903