Speaker
Description
I will present [O. Bengyat, A. Di Biagio, M. Christodoulou, M. Aspelmeyer, arXiv:2309.16312, submitted to PRL], where we argue for the equivalence between (i) an experimentally relevant Gravity Induced Entanglement (GIE) experiment and (ii) the original one, which is much less feasible and would require implementation in space. The original one comprises the interaction of two particles prepared in a superposition of two discrete paths [Bose et al, Phys. Rev. Lett. 119, 240401], [Marletto & Vedral Phys. Rev. Lett. 119, 240402]. The feasible one comprises a continuously delocalized (harmonic oscillator) state of motion [Krisnanda et al, npj Quantum Information 6, 12 (2020)]. An important open question has been whether these two different approaches allow to draw the same conclusions on the quantum nature of gravity. To answer this question, we use a path-integral approach to analyse a setup that contains both features: a superposition of two highly delocalized center of mass states. In both cases the appearance of entanglement, within linearised quantum gravity, is due to gravity being in a superposition of distinct geometries. Moreover, we are able to calculate the relativistic corrections to the entanglement. An experimental detection of those would be evidence for participation of both radiative and non-radiative degrees of freedom in GIE. This contributes to the debate around the matter, as the radiative degrees of freedom are considered the only ones relevant in the eyes of some [Anastopoulos et al, arXiv:2103.08044].
