Magnetic Levitation as a New Probe of Non-Newtonian Gravity

We present MORRIS (Magnetic Oscillatory Resonator for Rare-Interaction Studies) and propose the first tabletop search for non-Newtonian gravity due to a Yukawa-like fifth force using a magnetically levitated particle. Our experiment comprises a levitated sub-millimeter magnet in a superconducting trap that is driven by a time-periodic source. Featuring short-, medium-, and long-term stages, MORRIS will admit increasing sensitivities to the force coupling strength $α$, optimally probing screening lengths of $λ\sim 1,\mathrm{mm}$. Our short-term setup provides a proof-of-principle study, with our medium- and long-term stages respectively constraining $α\lesssim 10^{-4}$ and $α\lesssim 10^{-5}$, leading over existing bounds. Our projections are readily recastable to concrete models predicting the existence of fifth forces, and our statistical analysis is generally applicable to well-characterized sinusoidal driving forces. By leveraging ultralow dissipation and heavy test masses, MORRIS opens a new window onto tests of small-scale gravity and searches for physics beyond the Standard Model.

💡 Research Summary

The paper introduces MORRIS (Magnetic Oscillatory Resonator for Rare‑Interaction Studies), a tabletop experiment designed to probe non‑Newtonian gravity at the millimetre scale by searching for a Yukawa‑type fifth force. The authors motivate the work by noting that many beyond‑Standard‑Model (BSM) scenarios—such as extra dimensions, light moduli from string theory, or new massive gauge bosons—predict deviations from the inverse‑square law at distances of order 1 mm. Existing searches (torsion balances, pendulums, optically levitated microspheres) have either limited sensitivity at these distances or have not exploited magnetic levitation, which offers ultra‑low mechanical dissipation (quality factors Q ≳ 10⁶–10⁷) and the ability to suspend relatively massive (sub‑gram) test masses without active feedback noise.

The theoretical framework adopts the standard Yukawa parametrisation: (U(r) = -\frac{G_\infty m_s m_p}{r}\bigl