## Problem 048 — rank:61

**Title:** Single-cell state dynamics

**Added binding assumptions (LaTeX):**

```latex
Distinguish a chronologically followed cell, a sampled surviving lineage and a size-biased descendant at time $T$; their transition laws generally differ under state-dependent proliferation. Specify which one is validated and how division affects state. Snapshot densities alone constrain a flux divergence, not a unique drift; lineage data or explicit restrictions are necessary to remove the remaining equivalences.
```

**Direct edits:** 0. **Fresh external checks:** SC03