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arXiv · 2601.00651

Experimental exclusion of a generalized K\'arolyh\'azy gravity-induced decoherence model

Nicola Bortolotti·Kristian Piscicchia·Matthias Laubenstein·Simone Manti·Antonino Marcianò·Federico Nola·Catalina Curceanu
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Abstract

We report new experimental constraints on the generalized version of the gravity-induced decoherence model originally proposed by K\'arolyh\'azy. Using data collected by the VIP Collaboration at the INFN Gran Sasso National Laboratory with a high-purity germanium detector, we derive an improved lower bound on the spatial correlation length $R_K$ characterizing metric fluctuations in the model. We obtain a bound $R_K > 4.64$ m (95\% C.L.), which exceeds by more than an order of magnitude the previous experimental limit. When combined with the theoretical upper bound $R_K <1.98$ m derived from macroscopic localization requirements, our result excludes the generalized K\'arolyh\'azy model. The same conclusion applies to an associated non-Markovian formulation of the Continuous Spontaneous Localization (CSL) model. Our findings significantly tighten experimental constraints on gravity-related decoherence scenarios and demonstrate the sensitivity of underground low-background experiments to foundational modifications of quantum mechanics.

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Nicola Bortolotti, Kristian Piscicchia, Matthias Laubenstein, Simone Manti, Antonino Marcianò, Federico Nola, Catalina Curceanu. 2026-01-02. Experimental exclusion of a generalized K\'arolyh\'azy gravity-induced decoherence model. https://arxiv.org/abs/2601.00651

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