Our understanding of the universe is based on the existence of unknown forms of energy and matter. With roughly 70% of the total energy and more than 25% of the total mass budget they are expected to represent a macroscopic contribution. The research focuses now on the discovery of new sources after many favoured models could not be experimentally confirmed, yet.

Matter-wave interferometry is particularly well suited to detect energy forms like they are stored in canonical and non-canonical scalar fields. Due to their special properties these fields are also called chameleon or symmetron fields. Only in vacuum and with small densities the correlated forces can be measured by torsion balances or force sensors based on atom interferometry.

Prestudies were publishes by our collaborators Holger Müller and Sheng-wey Chiow in 2017. A significant expansion of the scanned parameter range can be reached with interferometry of compact and low-energy wave-packages, so called Bose-Einstein condensates (BEC), in free fall through a special test mass with interactions times of seconds.