Tests of Gravitational Inverse-Square Law in Submillimeter Regimes

Tests of the gravitational inverse-square law at submillimetre scales probe whether Newton’s law of universal gravitation holds at distances below one millimetre. Such experiments address fundamental questions about extra dimensions, new force carriers and deviations arising from theories of dark energy or modified gravity. A variety of techniques—torsion balances, micro-cantilevers, atomic and neutron interferometry, optomechanical resonators and precision oscillators—have been employed to search for Yukawa-type corrections or power-law deviations. These studies establish constraints on the strength and range of possible fifth forces, tighten bounds on compactification scales in higher-dimensional models and inform searches for new bosons in the sub-millimetre domain. The global significance lies in refining our understanding of gravity’s behaviour at short distances and guiding the design of future tabletop experiments, while practical applications emerge in precision metrology and the engineering of microelectromechanical systems.

Research from Nature Portfolio

Recent studies have proposed a novel quantum-mechanical approach that leverages the Josephson effect to detect minute phase shifts induced by gravitational potentials at millimetre and submillimetre scales. By integrating superconducting junctions into precision interferometers, the experiment promises sensitivity to parity-invariance tests of gravity and could bridge the gap between classical torsion balances and quantum sensors. The design outlines how gravitationally induced voltage variations influence the evolution of superconducting phases, offering a pathway to test Newtonian predictions with quantum coherence.

Tests of Gravitational Inverse-Square Law in Submillimeter Regimes publication trend

The graph below shows the total number of articles in tests of gravitational inverse-square law in submillimeter regimes across all publications each year (not limited to Nature Index journals).

Technical terms

Gravitational inverse-square law: The classical Newtonian relation in which the force between two masses decreases in proportion to the square of their separation.

Yukawa potential: A short-range modification of the inverse-square law that introduces an exponential decay term to describe forces mediated by massive bosons.

Josephson effect: The quantum tunnelling of superconducting Cooper pairs across a weak link, generating a phase-dependent current that can be sensitive to potential differences.

Torsion balance experiment: A sensitive device that measures tiny forces by observing the twist of a suspended rod or wire under gravitational or non-gravitational interactions.

Optomechanical levitated sensor: A system in which microscopic particles are trapped and manipulated by light, enabling precise measurements of force and displacement.

References

1. Proposal for a quantum mechanical test of gravity at millimeter scale. Scientific Reports (2024).
2. Micro-orbits in a many-brane model and deviations from Newton’s 1/r2 law. European Physical Journal C (2016).
3. Detecting large extra dimensions with optomechanical levitated sensors. European Physical Journal C (2019).