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arXiv · 2610.41024

Quantum amplification of improbable futures

Peter Maurice Catt
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Abstract

Some consequential futures consist of entirely plausible steps arranged into an unlikely sequence, such as ordinary weather anomalies combining into an extreme event or local equipment failures propagating into a widespread outage. Because the sequence as a whole carries little probability, it may be rarely observed in simulation. Quantum mechanics offers a way to change those odds: ideal amplitude amplification raises the chance of drawing such futures while preserving their relative likelihoods. For a five-state process six steps ahead, 13,888 of 15,625 futures are rare, yet together they account for about one draw in 40. We built the complete circuit in IBM's Qiskit and checked every part against an exact enumeration; four simulated rounds raised the share of rare futures drawn from 2.5% to 98.0%. On IBM's Kingston quantum computer, a two-step reference circuit that marks rare futures from a precomputed list drew them in 68.4% of shots against 43.5% for its control (z = 50); at three steps (about 1,170 two-qubit gates) the predicted signal reversed sign. Because this model's probabilities are known, every result could be checked against exact values; the mechanism is intended for simulators whose probabilities are hard to calculate, such as climate, epidemic and financial models.

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Peter Maurice Catt. 2026-10-29. Quantum amplification of improbable futures. https://arxiv.org/abs/2610.41024

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