SUMMARY
In the Standard Model of particle physics massive fermions (quarks and leptons) and bosons (W^+-, Z^o, H^o) are needed. However, the logic of nature requires that the universe emerged out of the vacuum and therefore all elementary particles should be massless. To test, whether this requirement is consistent with the mass structure of the Standard Model, corresponding mesonic states as well as the systems Z^o(91.2~GeV), W^+-(80.4~GeV) and 0^+(126~GeV) have been investigated in a unified theory of all forces including gravity, in which all needed parameters are constrained by basic boundary conditions.The results show indeed that for these states all basic boundary conditions are fulfilled. Thus, the quarks and massive bosons of the Standard Model should be interpreted as effective particles composed of massless elementary fermions and bosons, in full agreement with the structure of the universe.