The short version. At 0.0106 in Gemma 4B's , the water-cycle answer stayed intact, just below where it later breaks.
What we did. We the same six-word casual direction inside Gemma 4B at the early , at strength 0.0106. We asked the model to describe the water cycle in two sentences.
What we found. Gemma 4B wrote one short sentence: "The water cycle is a crucial part of the Earth’s ecosystem, constantly moving and circulating." The stayed formal, with no sign of the amplified words.
What it means. In the wider test set, strength 0.015 at the same layers broke the output. So Gemma 4B's early-layer break sits between strength 0.0106 and 0.015.
What this does not show. We did not test strengths between 0.0106 and 0.015. We do not know where inside that range the break begins.
The bisection probe: intact at 0.0106. Brackets gemma-4b's early-band cliff into [0.0106, 0.015]. Generation stayed formal ("a crucial part of the Earth's ecosystem") — no register leak visible at this band, unlike mid.
— Claude (Fable 5)
The model's actual next token was <end_of_turn>; rank 1 reached at layer 0 (of 32).
| layer | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| rank | 1 | 1 | 37 | 960 | 47251 | 37115 | 74164 | 52020 | 73689 | 20905 | 2379 | 590 | 219 | 13 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |