April 24, 2026
Light-based gravity sensing could improve groundwater, climate and underground monitoring
Study shows how optical technology can detect tiny gravity changes, with potential applications in environmental monitoring and navigation
A study by University of ÌìÃÀ´«Ã½ (UOW) physicist has demonstrated that gravity can subtly influence the behaviour of light, a breakthrough that could underpin future technologies for monitoring groundwater, tracking glacier melt, locating mineral deposits and detecting underground changes linked to volcanic activity and carbon storage.
The , published in Scientific Reports, shows early experimental evidence that photons – particles of light – interact with the Earth’s gravitational field in measurable ways, laying the groundwork for a new generation of ultra-sensitive gravity sensors.
Dr Li said the work could lead to more precise and compact next-generation sensing technologies for environmental monitoring, navigation and underground mapping.
“Tiny shifts in gravity can reveal critical changes beneath or around us, from underground water levels to magma build-ups below volcanos that could indicate future eruptions. Our research suggests light-based sensing technologies may one day provide a new way to detect and monitor those changes with very high precision,” Dr Li said.
Gravity sensing is already used in mining, infrastructure, defence and geoscience to “see” beneath the Earth’s surface by detecting differences in underground density of rocks, minerals, water or tunnels. However, photonic gravity sensors could offer advantages over conventional technologies through improved sensitivity, stability and miniaturisation.
Most current gravity sensors rely on mechanical systems that are susceptible to vibration and movement, limiting their use on moving platforms. Light-based sensing technologies could overcome those limitations, with the potential to produce gravity sensors that work reliably on moving platforms such as planes or submarines.
Dr Li said the findings also build on fundamental questions in physics dating back more than a century.
“In 1905, Albert Einstein postulated that the speed of light in a vacuum is constant and independent of the observer’s motion. Our experimental results suggest that photons can interact with the Earth’s gravitational field in ways that may influence how light transmits, which provides a new perspective on this longstanding assumption,” Dr Li said.
The work is at an early, proof-of-concept stage, and further development will be required before practical applications can be realised. Future research will focus on refining the measurement approach and exploring additional interactions between light and gravitational fields to better understand the underlying physics and potential technological uses.
About the research
‘Exploring the gravito-optic effect for gravity sensing applications’ by Enbang Li is published in Scientific Reports. ( )