Overview

There are several open fundamental questions in physics related to the interface of quantum mechanics and gravity. Examples are: How do quantum systems interact with gravity and is gravity quantized or not? How should the weak equivalence principle be formulated for quantum systems?

From the theoretical perspective, there are numerous models which describe the effect of gravity on quantum systems as well as the gravitational interaction of quantum systems, some taking quantum effects of gravity into account others not. Different models predict a different behaviour of quantum systems in free fall, and thus the observation of such system can give insights about the structure of spacetime.

To test models and their predictions, experiments are imperative. The corresponding experimental techniques have developed significantly during recent years, in particular, matter wave interferometry in free fall. Bremen with the Drop Tower at ZARM, Hannover with the infrastructure at HiTec and space projects of groups at the Leibniz University Hannover represent a large cluster of experience in this direction.

Therefore, this workshop will bring together experimentalist from the region and beyond as well as theoreticians working on the interaction of quantum systems and gravity. The goal is to discuss which aspects of the theoretical models can be tested in realistic experiments in free fall. What are the technical specifications an experiment would need to satisfy in order to test different models and what kind effects would be smoking gun signatures of physics beyond the standard model and general relativity?

The workshop is organized in collaboration of two European research networks, called COST Actions, whose goal is to search for traces of Quantum Gravity on largest and smallest scales (BridgeQG) and to find a consistent framework of relativistic quantum information theory (RQI). Both topics are closely related to the research of Quantum Frontiers, where quantum sensors are developed which will be able to measure the effect of gravity on quantum systems, and the theoretical foundations are developed to predict the behavior of quantum systems under the influence of gravity from different models which can be tested.