The 'arrow of time' might just be a lack of precision in our measurements, not chaos or entropy.
March 24, 2026
Original Paper
Precision's arrow of time
arXiv · 2603.22284
The Takeaway
Scientists have identified a third route to irreversibility called 'Precision-Induced Irreversibility,' where time effectively only moves forward because our world has a limited 'dynamic range' for recording data. It suggests that if you could record and calculate with infinite precision, the physical laws of our world would suddenly become reversible, allowing time to flow backward.
From the abstract
The arrow of time is usually attributed to two mechanisms: decoherence through environmental entanglement, and chaos through nonlinear dynamics. Here we demonstrate a third route, Precision-Induced Irreversibility (PIR), requiring neither. No entanglement. No nonlinearity. Just three ingredients: amplification, non-normality, and finite dynamic range, whose interplay yields an operational arrow of time; remove any one and reversibility can be restored. Non-Hermitian evolution remains mathematica