Experiment Rules Out a 60-Year-Old Gravity Decoherence Model

An underground detector at Italy's Gran Sasso lab found no trace of the faint radiation predicted by Frigyes Károlyházy's model, in which spacetime fluctuations destroy quantum superpositions, after 62 days of measurements. The result excludes this particular version of the model but does not rule out gravity's role in decoherence.

• A germanium crystal detector ran for 62 days beneath 1.4 km of rock
• No signal predicted by Károlyházy's 1960s model was found
• The result excludes the tested model version; other gravitational mechanisms remain possible
• The study was published in New Journal of Physics with FQxI support