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arXiv · 2507.02845

Enhancement of the effects due to the Schr\"odinger-Newton equation

Abstract

The Schr\"odinger-Newton (SN) equation introduces a nonlinear self-gravitational term to the standard Schr\"odinger equation, offering a paradigmatic model for semiclassical gravity. However, the small deviations it predicts from standard quantum mechanics pose significant experimental challenges. We propose a novel method to amplify such deviations through periodic modulation of the trapping frequency in a levitated mechanical oscillator. We identify specific regimes where the SN-induced effects on the dynamics of second moments are significantly enhanced-by up to six orders of magnitude compared to unmodulated setups. We show that this protocol remains feasible within current magnetic levitation technologies and enables distinguishability between standard and SN dynamics using measurable quantities such as the position variance. Our results pave the way for a viable experimental test of the SN equation, offering a new route to probe the interface between quantum mechanics and gravity.

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Davide Giordano Ario Altamura, José Luis Gaona-Reyes, Elliot Simcox, Hendrik Ulbricht, Angelo Bassi. 2025-07-03. Enhancement of the effects due to the Schr\"odinger-Newton equation. https://arxiv.org/abs/2507.02845

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