How Einstein's equivalence principle extends to the quantum world

How Einstein's equivalence principle extends to the quantum world has been puzzling physicists for decades, but a team including a University of Queensland researcher has found the key to this question.

UQ physicist, Dr. Magdalena Zych from the ARC Centre of Excellence for Engineered Quantum Systems, and the University of Vienna's Professor Caslav Brukner have been working to discover if quantum objects interact with gravity only through curved space-time.

"Einstein's equivalence principle contends that the total inertial and gravitational mass of any objects are equivalent, meaning all bodies fall in the same way when subject to gravity," Dr. Zych said.

"Physicists have been debating whether the principle applies to quantum particles, so to translate it to the quantum world we needed to find out how quantum particles interact with gravity.

"Werealised that to do this we had to look at the mass."