Can 'untranslatability' be measured? The three-way honorific register of Bengali and Hindi is grammatically forced but vanishes in English, so any translate-through-English pipeline must guess it back. A rule-based register classifier (precision ≥ 0.90 per class, both languages) is the instrument; the measurement quantifies the obstruction per sentence and tests, under pre-registration, whether it predicts downstream failure. Method and dataset held back pending arXiv.
Three independent agents that induce a game's hidden rules online, probe under uncertainty, and plan in an internal simulator. Rigorous offline evaluation (replay verifiers, held-out log pairs, baselines); modest live scores reported straight — best run 4/183 levels, aggregate ≈ 0.257% — with the exact broken invariants diagnosed rather than hidden.
A sub-quadratic O(n log n) structured replacement for self-attention, benchmarked forward-only on real Gemma-4-E2B and Llama-3.2-1B weights. Faster than dense attention past a ~1330-token crossover and monotonically further ahead out to 14k+ tokens. Reported as a speed/scaling result on an untrained gate — the efficiency characteristic, not modeling quality; mechanism held back pending write-up.