[R] Lag state in citation graphs: a systematic indexing blind spot with implications for lit review automation

Something kept showing up in our citation graph analysis that didn't have a name: papers actively referenced in recently published work but whose references haven't propagated into the major indices yet. We're calling it the lag state — it's a structural feature of the graph, not just a data quality issue.

The practical implication: if you're building automated literature review pipelines on Semantic Scholar or similar, you're working with a surface that has systematic holes — and those holes cluster around recent, rapidly-cited work, which is often exactly the frontier material you most want to surface.

For ML applications specifically: this matters if you're using citation graph embeddings, training on graph-derived features, or building retrieval systems that rely on graph proximity as a proxy for semantic relevance. A node in lag state will appear as isolated or low-connectivity even if it's structurally significant, biasing downstream representations.

The cold node functional modes (gateway, foundation, protocol) are a related finding — standard centrality metrics systematically undervalue nodes that perform bridging and anchoring functions without accumulating high citation counts.

Early-stage work, partially heuristic taxonomy, validation is hard. Live research journal with 16+ entries in EMERGENCE_LOG.md.