Testing for Quantum Gravity with Bose-Einstein Condensates

The multimode collaborative work `Non-gaussianity as a Signature of a Quantum Theory of Gravity’ between Hong Kong, Aix-Marseille and Oxford you, lead by Richard Howl and with the participation of Marios Christodoulou, Carlo Rovelli and Vlatko Vedral, has been published in PRX Quantum. Below is an accessible to the non-specialist summary. For over a hundred years, physicists …

Testing for Quantum Gravity with Bose-Einstein Condensates Read More »

Chiara Marletto featured at The Guardian

Chiara Marletto has been featured in the guardian,Chiara Marletto is a research fellow at Wolfson College, University of Oxford. Her research is in theoretical physics – especially quantum computation, thermodynamics and information theory. Her broader interests include theoretical biology, epistemology and Italian literature. The Science of Can and Can’t: A Physicist’s Journey Through the Land …

Chiara Marletto featured at The Guardian Read More »

Bob Wald
University of Chicago

Quantum Superposition of Massive Bodies

We analyse a gedankenexperiment previously considered by Mari et al. that involves quantum superpositions of charged and/or massive bodies (“particles”) under the control of the observers, Alice and Bob. In the electromagnetic case, we show that the quantization of electromagnetic radiation (which causes decoherence of Alice’s particle) and vacuum fluctuations of the electromagnetic field (which limits Bob’s ability to localize his particle to better than a charge-radius) both are essential for avoiding apparent paradoxes with causality and complementarity. We then analyze the gravitational version of this gedankenexperiment. We show that the analysis of the gravitational case is in complete parallel with the electromagnetic case provided that gravitational radiation is quantized and that vacuum fluctuations limit the localization of a particle to no better than a Planck length. This provides support for the view that (linearized) gravity should have a quantum field description.

Marcus Aspelmeyer
University of Vienna

On the role of gravity in table-top quantum experiments

I will discuss the challenges and prospects for isolating and exploring gravity as a relevant coupling mechanism in table-top quantum experiments. This includes quantum states of the metric generated by a quantum source mass and possible schemes to measure it. Experimentally, a central role is played by the possibility to achieve quantum control over motional states of levitated solid-state particles.