📘 ACM Framework: The "Trunk & Audit" Approach

📘 ACM 架构：基于“主干与审计”的动力学模型

Unified Baseline, Zero Ad-hoc Parameters. 统一基线，零即兴参数。

**1. What is the ACM Trunk Function?

什么是 ACM 主干函数？**

The ACM Trunk is a multi-stage dynamical operator that predicts galactic rotation curves across all acceleration regimes. Unlike MOND, which relies on a tunable interpolating function ($\nu$), ACM uses a rigid, nested response chain. ACM 主干函数是一个多级动力学算子，用于预测所有加速度制度下的星系旋转曲线。与依赖可调插值函数 ($\nu$) 的 MOND 不同，ACM 采用的是刚性的嵌套响应链。

• Rigidity (刚性): The Trunk parameters are fixed across the entire 164-galaxy sample. 主干参数在整个 164 个星系样本中是完全固定的。

• Predictability (可预测性): Any deviation from the Trunk is treated as a "Data Pathology" to be audited, not a "Model Failure" to be patched. 任何偏离主干的情况都被视为需要审计的“数据病理”，而非需要打补丁的“模型失效”。

**2. The Functional Hierarchy

函数的层级结构**

The Trunk Function processes the baryonic distribution through three logical layers: 主干函数通过三个逻辑层处理重子分布：

Geometric Scaling (几何缩放): Maps the baryonic mass into the global spatial manifold. 将重子质量映射到全局空间流形中。
Propagation Gradient (传导梯度): Calculates the dynamical response as a function of local density and global curvature. 计算作为局域密度和全局曲率函数的动力学响应。
Damping Correction (阻尼修正): Adjusts the response based on the inherent background resistance of the spatial grid. 根据空间网格固有的背景阻力调整响应。

**3. Why it outperforms MOND

为什么它优于 MOND**

Feature 特性	MOND	ACM
Logic 逻辑	Curve-fitting (曲线拟合)	Forensic Audit (法医审计)
Parameters 参数	$a_0$ + Interpolation (可调)	Rigid Trunk (固定主干)
Outliers 离群值	Ignored or patched (忽略或打补丁)	Diagnosed as Pathology (诊断为病理)
Consistency 一致性	Galaxy-dependent (依赖具体星系)	Universal Baseline (全局统一基线)

**4. The 3-Step Audit Workflow

三步审计工作流**

When a galaxy shows a high residual against the ACM Trunk, we perform a Forensic Audit: 当星系对 ACM 主干表现出高残差时，我们进行法医审计：

Distance Sensitivity ($D$): Test if the residual vanishes at the $D \pm e_D$ edge. (Common in Geometry Hostages) 距离敏感度：测试残差是否在距离误差边缘消失。（常见于“几何人质”）
Stellar Normalization ($M/L$): Evaluate if a conservative $M/L$ shift restores the ACM baseline. (Common in Stellar Hostages) 恒星归一化：评估保守的 $M/L$ 偏移是否能恢复 ACM 基线。（常见于“恒星人质”）