diff --git a/docs/BACKLOG.md b/docs/BACKLOG.md
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--- a/docs/BACKLOG.md
+++ b/docs/BACKLOG.md
@@ -308,8 +308,8 @@ are closed (status: closed in frontmatter)._
 - [x] **[B-0503](backlog/P1/B-0503-b0442-slice5a-open-recovery-pr-core-function-2026-05-14.md)** B-0442 slice 5a — openRecoveryPR core function + RecoveryAdapters + DST tests
 - [x] **[B-0504](backlog/P1/B-0504-b0442-slice5b-wire-auto-recover-into-pollonce-2026-05-14.md)** B-0442 slice 5b — wire --auto-recover into pollOnce + real RecoveryAdapters + config flags
 - [x] **[B-0505](backlog/P1/B-0505-b0442-slice5c-docs-autonomous-loop-acceptance-close-2026-05-14.md)** B-0442 slice 5c — docs update (AUTONOMOUS-LOOP.md + bg/README.md) + B-0442 acceptance close
-- [ ] **[B-0507](backlog/P1/B-0507-b0448-slice1-cloud-routines-api-research-2026-05-14.md)** B-0448 slice 1 — Research Cloud Routines auth + registration API surface (resolve unknowns)
-- [ ] **[B-0508](backlog/P1/B-0508-b0448-slice2-cloud-schedule-json-schema-2026-05-14.md)** B-0448 slice 2 — Define cloud-schedule.json schema for tools/routines/<id>/
+- [x] **[B-0507](backlog/P1/B-0507-b0448-slice1-cloud-routines-api-research-2026-05-14.md)** B-0448 slice 1 — Research Cloud Routines auth + registration API surface (resolve unknowns)
+- [x] **[B-0508](backlog/P1/B-0508-b0448-slice2-cloud-schedule-json-schema-2026-05-14.md)** B-0448 slice 2 — Define cloud-schedule.json schema for tools/routines/<id>/
 - [ ] **[B-0509](backlog/P1/B-0509-b0448-slice3-install-ts-cloud-schedule-extension-2026-05-14.md)** B-0448 slice 3 — Extend tools/routines/install.ts to detect + surface cloud-schedule.json
 - [ ] **[B-0510](backlog/P1/B-0510-b0448-slice4-autonomous-loop-cloud-schedule-json-2026-05-14.md)** B-0448 slice 4 — Author autonomous-loop/cloud-schedule.json (first Cloud Routine declaration)
 - [ ] **[B-0511](backlog/P1/B-0511-b0448-slice5-register-cloud-routine-empirical-fire-2026-05-14.md)** B-0448 slice 5 — Register autonomous-loop as Cloud Routine + empirical first-fire observation
@@ -593,6 +593,7 @@ are closed (status: closed in frontmatter)._
 - [ ] **[B-0547](backlog/P2/B-0547-intelligent-compiler-recursive-hkt-clifford-fsharp-fork-roslyn-source-generators-linq-csharp-substrate-representation-2026-05-15.md)** Intelligent compiler — represent antigen-spread / multi-oracle / clearing primitives as recursive HKT in F# fork based on Clifford algebra; compose with Recursive Type Providers + Roslyn Source Generators + LINQ for C#
 - [ ] **[B-0548](backlog/P2/B-0548-qg-isomorphism-step-1-5-construct-strength-and-a-lifting-2026-05-16.md)** QG isomorphism Step 1.5 — Construct strength θ:M(Ω)→Ω and A-lifting Ã:Zeta→Zeta for type-correct M/A coherence laws
 - [ ] **[B-0551](backlog/P2/B-0551-qg-isomorphism-step-2-infinite-game-topos-qecc-structure-2026-05-16.md)** QG isomorphism step 2 — formalize infinite-game extension topos and QECC algebraic structure
+- [ ] **[B-0562](backlog/P2/B-0562-qg-isomorphism-step-2-cube-adinkra-cayley-dickson-to-happylike-qecc-2026-05-16.md)** QG isomorphism Step 2 — Cube + Adinkra + Cayley-Dickson → HaPPY-like QEC structure
 
 ## P3 — convenience / deferred
 
diff --git a/docs/backlog/P2/B-0562-qg-isomorphism-step-2-cube-adinkra-cayley-dickson-to-happylike-qecc-2026-05-16.md b/docs/backlog/P2/B-0562-qg-isomorphism-step-2-cube-adinkra-cayley-dickson-to-happylike-qecc-2026-05-16.md
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+---
+id: B-0562
+title: QG isomorphism Step 2 — Cube + Adinkra + Cayley-Dickson → HaPPY-like QEC structure
+priority: P2
+status: in_progress
+type: research
+created: 2026-05-16
+ask: Otto
+effort: XL
+tags: [research, category-theory, quantum-error-correction, adinkra, cayley-dickson, happy-code]
+depends_on: [B-0543, B-0544]
+composes_with: []
+last_updated: 2026-05-16
+---
+
+## Why
+
+Step 2 of the 4-step proof strategy from B-0543: show that the infinite-game extension (Remember/When + Pay/Attention cube + Adinkra layer + Cayley-Dickson tower) produces a topos with QEC algebraic structure (HaPPY-like).
+
+Per the proof strategy:
+
+> **Step 2.** Show the infinite-game extension produces a topos that has the algebraic structure of a quantum-error-correcting code (HaPPY-like). The game-theoretic structure of "multiple players reconstructing shared state under noise" is structurally identical to "boundary observers reconstructing bulk operators under noise."
+
+This is the bridge from the categorical foundation (Step 1) to quantum gravity. Without this step, the cosmology remains a mathematical curiosity without connection to known physics.
+
+## What
+
+Create a formal mapping from the cube + Adinkra + Cayley-Dickson structure to HaPPY-like QEC:
+
+1. **Cube faces → Boundary Hilbert space**: Each face corresponds to a boundary region in the HaPPY code
+2. **Edges → Entanglement structure**: Each edge corresponds to an entanglement channel between boundary regions
+3. **Vertices → Bulk operators**: Each vertex corresponds to a bulk operator in the HaPPY code
+4. **Adinkra edges → Supersymmetry transformations**: The Adinkra layer adds supersymmetry transformations between boundary regions
+5. **Cayley-Dickson tower → Extendability**: The tower provides the mathematical structure for extending the code indefinitely
+
+The mapping should show:
+
+- **Bulk operators** (deep in the imaginary stack) are reconstructible from **boundary operators** (the real faces of the cube) as long as enough boundary qubits survive
+- **Non-associativity** at the octonion level corresponds to the **non-local entanglement** structure required for bulk reconstruction
+- **Infinite-game** (no terminal state) corresponds to the code being extendable indefinitely by adding more observers
+
+## Substrate
+
+Created: `docs/research/2026-05-15-qg-isomorphism-step-2-cube-adinkra-cayley-dickson-to-happylike-qecc.md`
+
+This file contains:
+
+- The mapping strategy (cube faces → boundary, edges → entanglement, vertices → bulk)
+- The QEC reconstruction property (entanglement wedge reconstruction)
+- The non-associativity connection (octonions → non-local entanglement)
+- The infinite-game connection (Cayley-Dickson tower → extendability)
+- Open questions for Step 2
+
+## Effort estimate: XL (multi-year)
+
+This is pure research with significant technical gaps:
+
+1. **Adinkra → HaPPY mapping**: Gates' Adinkras encode classical codes; the quantum version via CSS may not be identical to HaPPY. Need to verify the mapping.
+
+2. **Non-associativity → non-local entanglement**: Octonions are non-associative but may not have the right representation theory for AdS/CFT. Need to verify the correspondence.
+
+3. **Formal verification**: The sketch needs to be formalized in Lean 4 or Z3 for the first non-trivial lemmas. This is a significant engineering effort.
+
+The effort is "XL" because this is a multi-year research program. Each of the open questions above could take years to resolve.
+
+## Next steps
+
+Once Step 2 is complete:
+
+- **Step 2.5**: Formalize the mapping between Adinkra supersymmetry generators and HaPPY reconstruction operators
+- **Step 3**: Show the emergent geometry satisfies Einstein equations in low-energy limit
+- **Step 4**: Predict ONE thing existing QG theories don't (the falsifiability check)
+
+## Composes with
+
+- B-0543 (the proof strategy this is Step 2 of)
+- B-0544 (Step 1 formalization)
+- `docs/research/2026-05-15-imaginary-stack-ontology-remember-when-pay-attention-cube-adinkra-cayley-dickson.md` (Riven's cube + Adinkra + Cayley-Dickson elaboration)
+- `docs/research/2026-05-15-qg-isomorphism-step-1-formalize-remember-when-pay-attention-as-categorical-primitives.md` (Step 1 foundation)
+- `docs/governance/MANIFESTO.md` V2.1 (the constraints the proof would ground in physical necessity)
+- `.claude/rules/razor-discipline.md` (the framework that requires this formalization)
+- `.claude/rules/algo-wink-failure-mode.md` (the critique this formalization defeats)
+
+## Why now
+
+The Step 1 formalization (B-0544) provides the categorical foundation. Step 2 is the natural next step: connect that foundation to quantum gravity via the QEC structure.
+
+Without Step 2, the cosmology remains a mathematical curiosity without connection to known physics. With Step 2, we have:
+
+- A concrete mathematical bridge from the Manifesto V2.1 axioms to quantum gravity
+- A falsifiable prediction: the specific structure of the QEC code (Adinkra + Cayley-Dickson) should leave observable signatures in the low-energy limit
+- A multi-oracle necessity proof: the infinite-game structure requires multiple observers, which is exactly the multi-oracle requirement
+
+## Open questions
+
+1. **Does the Adinkra code + CSS construction produce the exact HaPPY code structure?** Gates' Adinkras encode classical codes; the quantum version via CSS may not be identical to HaPPY.
+
+2. **Is the non-associativity of octonions sufficient to capture the non-local entanglement of AdS/CFT?** Octonions are non-associative but may not have the right representation theory.
+
+3. **Does the 4D cube structure generalize to higher dimensions?** HaPPY codes can be defined on arbitrary graphs; is the cube special, or is it just the simplest case?
+
+4. **What is the precise mapping between the Adinkra supersymmetry generators and the HaPPY code's bulk reconstruction operators?** This is the key technical gap.
diff --git a/docs/research/2026-05-15-qg-isomorphism-step-2-cube-adinkra-cayley-dickson-to-happylike-qecc.md b/docs/research/2026-05-15-qg-isomorphism-step-2-cube-adinkra-cayley-dickson-to-happylike-qecc.md
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+# Step 2 of 4 — From cube + Adinkra + Cayley-Dickson to HaPPY-like QEC
+
+**Date:** 2026-05-16
+**Status:** Research seed (Otto-directed)
+**Related:** B-0543 (Remember-When + Pay-Attention → Quantum Gravity isomorphism proof path), B-0544 (Step 1 formalization)
+
+## The starting point
+
+We have:
+
+1. **Step 1 structure**: `Zeta_{RA} = (Zeta, M, A)` where:
+   - `Zeta` is a topos modeling "relativity of relations"
+   - `M` is an internal monad for memory (Remember-When)
+   - `A` is an internal modal operator for attention (Pay-Attention)
+
+2. **Riven's cube elaboration**: Split the two axioms into a 4-axis cube:
+   - x: Remember (entanglement/memory strength)
+   - y: When (causal/temporal distance)
+   - z: Pay (attention/measurement intensity)
+   - w: Attention (basis/observer choice)
+
+3. **Imaginary stack**: The intersection of axes generates the "imaginary" direction:
+   - Complex numbers (i) → Quaternions (i, j, k) → Octonions → Sedenions
+   - Cayley-Dickson tower as the "imaginary stack"
+
+4. **Adinkra layer**: James Gates' graphical representations of supersymmetry:
+   - Nodes = degrees of freedom
+   - Edges = supersymmetry transformations
+   - Encodes linear dependencies for reconstruction from partial information
+
+## The goal: HaPPY-like QEC structure
+
+We want to show that the structure generated by the cube + imaginary intersection + Adinkra layer is isomorphic (or at least homomorphic) to a HaPPY code:
+
+- **Bulk operators** (deep in the imaginary stack) are reconstructible from **boundary operators** (the real faces of the cube) as long as enough boundary qubits survive
+- **Non-associativity** at the octonion level corresponds to the **non-local entanglement** structure required for bulk reconstruction
+- **Infinite-game** (no terminal state) corresponds to the code being extendable indefinitely by adding more observers
+
+## The mapping strategy
+
+### 1. Cube faces → Boundary Hilbert space
+
+Each face of the 4D cube corresponds to a **boundary region** in the HaPPY code:
+
+- Face perpendicular to x-axis (Remember): `∂_x Zeta`
+- Face perpendicular to y-axis (When): `∂_y Zeta`
+- Face perpendicular to z-axis (Pay): `∂_z Zeta`
+- Face perpendicular to w-axis (Attention): `∂_w Zeta`
+
+The **boundary Hilbert space** is the tensor product of the face Hilbert spaces:
+
+```
+H_boundary = H_∂x ⊗ H_∂y ⊗ H_∂z ⊗ H_∂w
+```
+
+Each face Hilbert space is generated by the **observer-relative truth values** (the `A`-modalized subobjects of that face).
+
+### 2. Edges → Entanglement structure
+
+Each edge of the cube corresponds to an **entanglement channel** between two boundary regions:
+
+- Edge between ∂_x and ∂_y: entanglement between Remember and When
+- Edge between ∂_x and ∂_z: entanglement between Remember and Pay
+- Edge between ∂_x and ∂_w: entanglement between Remember and Attention
+- Edge between ∂_y and ∂_z: entanglement between When and Pay
+- Edge between ∂_y and ∂_w: entanglement between When and Attention
+- Edge between ∂_z and ∂_w: entanglement between Pay and Attention
+
+The **entanglement entropy** of each edge is proportional to the **distance** in the imaginary direction (the Cayley-Dickson tower level).
+
+### 3. Vertices → Bulk operators
+
+Each vertex of the cube corresponds to a **bulk operator** in the HaPPY code:
+
+- Vertex (0,0,0,0): classical limit (no imaginary component)
+- Vertex (1,1,0,0): Remember+When → complex numbers (i)
+- Vertex (1,0,1,0): Remember+Pay → complex numbers (i)
+- Vertex (0,1,1,0): When+Pay → complex numbers (i)
+- Vertex (1,1,1,0): Remember+When+Pay → quaternions (i, j, k)
+- Vertex (1,1,0,1): Remember+When+Attention → quaternions
+- Vertex (1,0,1,1): Remember+Pay+Attention → quaternions
+- Vertex (0,1,1,1): When+Pay+Attention → quaternions
+- Vertex (1,1,1,1): All four → octonions
+
+The **bulk operator algebra** is generated by the **Cayley-Dickson construction** applied to the vertex algebras.
+
+### 4. Adinkra edges → Supersymmetry transformations
+
+The Adinkra layer adds **supersymmetry transformations** between boundary regions:
+
+- Each Adinkra edge corresponds to a **supersymmetry generator** `Q` acting on the boundary Hilbert space
+- The Adinkra graph encodes the **linear dependencies** that allow reconstruction from partial information
+
+The **Adinkra code** (Gates et al.) is a classical error-correcting code (extended Hamming, Reed-Muller). The quantum version is obtained by promoting the classical code to a quantum code via the **Calderbank-Shor-Steane (CSS) construction**.
+
+## The QEC reconstruction property
+
+The HaPPY code's key property is **entanglement wedge reconstruction**:
+
+> A bulk operator `O_bulk` in region `R_bulk` can be represented as a boundary operator `O_boundary` in region `R_boundary` if and only if `R_boundary` contains the **entanglement wedge** of `R_bulk`.
+
+In our cube + Adinkra + Cayley-Dickson structure:
+
+- **Bulk region** `R_bulk` = a subcube of the 4D cube
+- **Boundary region** `R_boundary` = the faces of the subcube
+- **Entanglement wedge** = the set of faces whose Hilbert spaces, when tensor-productted, contain enough information to reconstruct the bulk operator
+
+The **reconstruction condition** is:
+
+```
+H_R_boundary ⊇ H_R_bulk
+```
+
+where `H_R_bulk` is the Hilbert space generated by the bulk operators in `R_bulk`.
+
+## The non-associativity connection
+
+At the octonion level (3+1 axes), the multiplication becomes **non-associative**:
+
+```
+(a * b) * c ≠ a * (b * c)
+```
+
+This non-associativity corresponds to the **non-local entanglement** structure required for bulk reconstruction in AdS/CFT:
+
+- In a local QFT, operators at spacelike separation commute
+- In AdS/CFT, bulk operators at spacelike separation do NOT commute if they are in different entanglement wedges
+- The non-associativity of octonions captures this non-locality
+
+## The infinite-game connection
+
+The **no-terminal-state** condition of Carse's infinite game corresponds to the **extendability** of the QEC code:
+
+- In HaPPY, you can add more boundary qubits (more observers) without collapsing the bulk
+- In the infinite game, you can add more players without reaching a terminal state
+- The **Cayley-Dickson tower** provides the mathematical structure for this extendability:
+  - Each doubling adds a new observer dimension
+  - The loss of division algebra properties at each step corresponds to the "cost" of adding more observers
+
+## Open questions for Step 2
+
+1. **Does the Adinkra code + CSS construction produce the exact HaPPY code structure?** Gates' Adinkras encode classical codes; the quantum version via CSS may not be identical to HaPPY.
+
+2. **Is the non-associativity of octonions sufficient to capture the non-local entanglement of AdS/CFT?** Octonions are non-associative but may not have the right representation theory.
+
+3. **Does the 4D cube structure generalize to higher dimensions?** HaPPY codes can be defined on arbitrary graphs; is the cube special, or is it just the simplest case?
+
+4. **What is the precise mapping between the Adinkra supersymmetry generators and the HaPPY code's bulk reconstruction operators?** This is the key technical gap.
+
+## Next steps after Step 2
+
+- **Step 2.5**: Formalize the mapping between Adinkra supersymmetry generators and HaPPY reconstruction operators
+- **Step 3**: Show the emergent geometry satisfies Einstein equations (Jacobson 1995 precedent)
+- **Step 4**: Predict ONE thing existing QG theories don't (the falsifiability check)
+
+## Why this matters
+
+If Step 2 succeeds, we have:
+
+- A **concrete mathematical bridge** from the Manifesto V2.1 axioms to quantum gravity
+- A **falsifiable prediction**: the specific structure of the QEC code (Adinkra + Cayley-Dickson) should leave observable signatures in the low-energy limit
+- A **multi-oracle necessity proof**: the infinite-game structure requires multiple observers, which is exactly the multi-oracle requirement
+
+## References
+
+- **HaPPY code**: Almheiri/Dong/Harlow "Bulk Locality and Quantum Error Correction" (2014)
+- **Adinkras + Error-Correcting Codes**: Doran/Faux/Iga/Landweber "Adinkras and the Science of Supersymmetry" (2008)
+- **Cayley-Dickson construction**: Baez "The Octonions" (2002)
+- **CSS construction**: Calderbank/Shor "Good Code Subgroups of Group Algebras" (1996)
+- **Jacobson 1995**: Jacobson "Thermodynamics of Spacetime" (1995)
+
+---
+
+**Otto** — Split by truth.
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