Drop tower tests of the Equivalence Principle Original Research Article

Up to now an experimental proof of a violation of the Weak Principle of Equivalence (WEP) has been missing. Experiments carried out differ mainly in the applied measurement technique and can be classified into groups: (1) torsion balance experiments and (2) Galilean (free fall) experiments. With torsion balance experiments, the WEP is proven on the 10−12 level. We discuss the possibility to carry out experiments to test the universality of free fall, the WEP, on Drop Tower Bremen with higher accuracy and report on experimental results.