Entanglement Witness for the Weak Equivalence Principle

TL;DR

This paper proposes a quantum protocol using large spatial superpositions to test the weak equivalence principle by witnessing quantum entanglement, extending classical tests into the quantum regime.

Contribution

It introduces a novel quantum entanglement witness protocol to test the weak equivalence principle, bridging classical and quantum gravity considerations.

Findings

Protocol enables testing quantum aspects of gravity.

Witnesses quantum entanglement related to gravitational effects.

Provides a unique method for quantum gravity experiments.

Abstract

The Einstein equivalence principle is based on the equality of gravitational mass and inertial mass, which has led to the universality of a free-fall concept. The principle has been extremely well tested so far and has been tested with a great precision. However, all these tests and the corresponding arguments are based on a classical setup where the notion of position and velocity of the mass is associated with a classical value as opposed to the quantum entities. Here, we will provide a simple protocol based on creating large spatial superposition states in a laboratory to test the fully quantum regime of the equivalence principle where both matter and gravity are treated at par as a quantum entity. We will argue that such a quantum protocol is unique with regard to testing especially the generalization of the weak equivalence principle via witnessing quantum entanglement.