The weak equivalence principle (WEP) is the cornerstone of general relativity (GR). Testing
it is thus a natural way to confront GR to experiments, which has been pursued for four …

In the search for clues to the matter–antimatter puzzle, experiments with atoms or molecules
play a particular role. These systems allow measurements with very high precision, as …

Here we review the field of atom chips in the context of Bose–Einstein Condensates (BEC)
as well as cold matter in general. Twenty years after the first realization of the BEC and 15 …

The potential of precision spectroscopy as a tool in systematic searches for effects of Lorentz
and CPT violation is investigated. Systems considered include hydrogen, antihydrogen …

Many effective field theories describing gravity cannot arise from an underlying theory based
on Riemann geometry or its extensions to include torsion and nonmetricity but may instead …

Clock-comparison experiments are among the sharpest existing tests of Lorentz symmetry in
matter. We characterize signals in these experiments arising from modifications to electron …

We review the main arguments against antigravity, a different acceleration of antimatter
relative to matter in a gravitational field, discussing and challenging Morrison's, Good's and …

Performing measurements of the properties of antihydrogen, the bound state of an
antiproton and a positron, and comparing the results with those for ordinary hydrogen, has …

Experiments with antihydrogen (H¯) for a study of matter-antimatter symmetry and antimatter
gravity require ultracold H¯ to reach ultimate precision. A promising path towards antiatoms …

The Standard-Model Extension (SME) provides a comprehensive effective field-theory
framework for the study of CPT and Lorentz symmetry. This work reviews the structure and …