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arXiv · 2509.17163

Quantum Late-Time Decay and Channel Dependence

Francesco Giacosa·Anna Kolbus·Krzysztof Kyziol·Magdalena Plodowska·Milena Piotrowska·Karol Szary·Arthur Vereijken
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Abstract

Quantum mechanics predicts deviations from exponential decay at short and long times, yet experimental evidence is limited. We report a power-law tail after $\sim$10 lifetimes in two fluorescent compounds (erythrosine~B and eosine Y), confirmed by two detectors probing distinct bands but yielding different power coefficients. The data match a divergent but normalizable spectral density, and theory predicts oscillations as a future test. A novel and general result is that in multichannel QM (and QFT) decay, the lifetime is universal, but the late-time deviations are channel- (or band-) dependent, a feature consistent with our data.

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Francesco Giacosa, Anna Kolbus, Krzysztof Kyziol, Magdalena Plodowska, Milena Piotrowska, Karol Szary, Arthur Vereijken. 2025-09-21. Quantum Late-Time Decay and Channel Dependence. https://arxiv.org/abs/2509.17163

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