300-year-old Cavendish experiment could become the world’s best dark matter detector

Researchers propose turning Cavendish’s torsion balance into a resonant detector for axion dark matter.

The concept could, in theory, outperform current searches such as ADMX and reach new axion mass ranges.

Its appeal is low cost and extreme sensitivity, but the idea remains unproven.

Major hurdles include thermal noise, vibration isolation, and difficult engineering at femtonewton scales.