# 📐 L2 Spec — Magnetic Resonance Elastography (MRE) Mismatch-Only Spec
**ID:** `L2-055-001` · **Status:** ⊙ Testnet (genesis catalog)
**Parents:** ⬆ Principle [`L1-055`](/artifact/l1/L1-055)
> **🎯 Tolerance (ε):** expression
> **⚖ Difficulty score:** 0.5 · **Delta tier:** 5
> **⛓ On-chain block:** 41553375
---
## 1. Domain Ω
**Type:** `range`
| Parameter | Unit | Range |
|---|---|---|
| H | px | 64 |
| W | px | 64 |
| Z | — | 8 – 128 |
| Snr db | dB | 0.0 – 35.0 |
| F mech hz | Hz | 20 – 200 |
| Motion artifact | — | 0.0 – 0.3 |
| Wave reflections | — | 0.0 – 0.5 |
| Tissue anisotropy | — | 0.0 – 0.3 |
| Inversion reg error | — | 0.0 – 0.3 |
## 2. Tolerance (ε)
**Type:** `fn`
```
11.0 + 0.3 * SNR_dB - 10.0 * wave_reflections - 6.0 * tissue_anisotropy - 6.0 * motion_artifact
```
## 3. Difficulty
| Property | Value |
|---|---|
| Difficulty score | 0.5 |
| Delta tier | 5 |
## 4. Fingerprint
`9ed7feb1a56f07fe00985a858cc4fe912b4eb156cb76db9d71c0bf1bac8171db`
## 5. On-chain Registration
- **Chain hash:** `0x54b1cc492fce7e77d4e549d8447b89b58617d611f0f27c2dde68cebd606897ed`
- **Chain tx hash:** `0xe9afd39b351d65aad9829558ddfa2a50de921f5fee09a44b21fb7ea85c252c0e`
- **Chain block:** `41553375`
---
## File Mapping
This bundle consists of: `L2-055-001.md`, `L2-055-001.json`.
| File | Role | How to regenerate |
|------|------|-------------------|
| `L2-055-001.md` | Source of truth — edit this | Human or LLM |
| `L2-055-001.json` | Structured metadata for the registry | LLM regenerates from the sections above |
**Prompt for your LLM after editing this Markdown:**
> Read the attached Markdown. Regenerate the sibling `.json` so every field matches.
> Preserve the schema documented in the rows above.
> Output each file in its own fenced code block tagged with the filename.
> Output only the JSON object.
_This Markdown was auto-synthesized from the catalog row for `L2-055-001`._
_Edit it, regenerate the JSON, and submit at [/submit](/submit) to claim the artifact._