Quantum systems for gravitational entanglement

How quantum is gravity? This question still represents the gaping hole in our understanding of fundamental physics.

This group is focused on experiments that study gravity in quantum systems. Prior experiments with spatial quantum superpositions of atoms revealed that a gravitational measurement follows the rules of a quantum interaction [1].

But can a gravitational field also be in a quantum superposition? To answer this question, we want to prepare macroscopic particles in quantum states and study their gravitational interaction. The ultimate goal is to use such quantum states to create quantum entanglement mediated just by gravity and, therefore, demonstrate the quantum nature of gravity [2-5].



[1] C. Overstreet / P. Asenbaum,  M. Kim, J. Curti, M. A. Kasevich, Observation of a gravitational Aharonov-Bohm effect, Science 375, 226(2022)



[2] C. Marletto, V. Vedral, Gravitationally Induced Entanglement between Two Massive Particles is Sufficient Evidence of Quantum Effects in Gravity
Phys. Rev. Lett. 119, 240402 (2017), https://doi.org/10.1103/PhysRevLett.119.240402

[3] S. Bose, A. Mazumdar, G. W. Morley, H. Ulbricht, M. Toroš, M. Paternostro, A. A. Geraci, P. F. Barker, M. S. Kim, G. Milburn
Spin Entanglement Witness for Quantum Gravity, Phys. Rev. Lett. 119, 240401 (2017), https://doi.org/10.1103/PhysRevLett.119.240401

[4] T. Krisnanda, G. Y. Tham, M. Paternostro, T. Paterek, Observable quantum entanglement due to gravity. npj Quantum Inf 6, 12 (2020). https://doi.org/10.1038/s41534-020-0243-y

[5] D. Carney, Newton, entanglement, and the graviton, Phys. Rev. D 105, 024029 (2022), https://doi.org/10.1103/PhysRevD.105.024029