Our paper arXiv:2101.11629 contains a technical error which changes some of the conclusions. We thank Streltsov, Pedernales, and Plenio for bringing the essence of this error to our attention. Here we explain the error, examine its consequences, and suggest methods to overcome the resulting weakness in the proposed experiment.

1 aCarney, Daniel1 aMüller, Holger1 aTaylor, Jacob, M. uhttps://arxiv.org/abs/2111.0466701340nas a2200133 4500008004100000245006500041210006500106260001400171520092300185100001901108700002001127700002201147856003701169 2021 eng d00aTesting quantum gravity with interactive information sensing0 aTesting quantum gravity with interactive information sensing c1/27/20213 aWe suggest a test of a central prediction of perturbatively quantized general relativity: the coherent communication of quantum information between massive objects through gravity. To do this, we introduce the concept of interactive quantum information sensing, a protocol tailored to the verification of dynamical entanglement generation between a pair of systems. Concretely, we propose to monitor the periodic wavefunction collapse and revival in an atomic interferometer which is gravitationally coupled to a mechanical oscillator. We prove a theorem which shows that, under the assumption of time-translation invariance, this collapse and revival is possible if and only if the gravitational interaction forms an entangling channel. Remarkably, as this approach improves at moderate temperatures and relies primarily upon atomic coherence, our numerical estimates indicate feasibility with current devices.

1 aCarney, Daniel1 aMüller, Holger1 aTaylor, Jacob, M. uhttps://arxiv.org/abs/2101.11629