Quantum generalisation of Einstein's Equivalence Principle can be verified with entangled clocks as quantum reference frames

Understand

The Einstein Equivalence Principle (EEP) is of crucial importance to test the foundations of general relativity.

• When the particles involved in the test exhibit quantum properties, it is unknown whether this principle still holds.
• A violation of the EEP would have drastic consequences for physics.
• A more conservative possibility is that the EEP holds in a generalised form for delocalised quantum particles.