AI RESEARCH

When and How Long? The Readout-Mediator Angle in Temporal Reasoning

arXiv CS.AI

ArXi:2605.29126v1 Announce Type: cross A linear probe can decode a representation almost perfectly and yet be completely irrelevant to how the model uses it. On calendar-date duration reasoning in language models, a $\sin$/$\cos$ probe recovers day-of-year from a layer's activations, yet ablating its direction has no effect on the model's answers -- while ablating a four-dimensional subspace found by Distributed Alignment Search (DAS) at the same layer collapses performance entirely.