[en] The condition for the calculation of radiative corrections is to renormalize the based theory. Because of the complex structure and the multiplicity of parameters and fields it is not uniquely determined how the renormalization of the standard model of the electroweak interactions is to be performed in a consistent way. The present thesis yields some contribution to this question. A renormalization scheme for the Glashow-Salam-Weinberg model was discussed in which the masses of the gauge bosons, the Higgs mass, the fermion masses, and the fine structure constant are the fundamental parameters. The Slavnov-Taylor identities following from the gauge invariance were extensively discussed and their consequences for the renormalization procedure studied. As concrete application the radiative corrections to the μ-decay and to the ν_μe- respectively anti ν_μe-scattering were studied in the 1-loop approximation. In order to compare the statements of the standard model with the experimental results we have on the one hand by means of the masses M_W and M_Z calculated the μ decay width and the ratio of the cross sections σ(ν_μe→ν_μe)/σ(anti ν_μe→anti ν_μe) and compared with the data. On the other hand we have from the comparison of these quantities with the experimentally determined values calculated the gauge boson masses. (orig./HSI)

[en] Explanations of the recently observed high-Q², large-x events in deep-inelastic positron-proton scattering at HERA proposed in the literature are reviewed. Scenarios with generic leptoquarks or with squarks in supersymmetry with R-parity violation, and contact terms are discussed. Possibilities to test these scenarios at other experiments are investigated. (orig.)

[en] We study a functional method to extract the V-A condensate of dimension 6 from a comparison of τ-decay data with the asymptotic space-like QCD prediction. Our result is in agreement within errors with that from conventional analyses based on finite energy sum rules

[en] We present analytic formulas and numerical results for the complete electroweak radiative corrections of O(α³) to charged current deep inelastic electron-proton scattering at HERA energies. The calculations are performed in the framework of the quark parton model and the electroweak standard theory. Hard bremsstrahlung contributions integrated over the full available phase space are included. (orig.)

[en] The characteristic features of electroweak radiative corrections in deep-inelastic scattering at HERA are reviewed. Numerical results are presented and consequences for the application of radiative corrections are discussed. (author)

[en] In the light of recent HERA data, we analyze the connection between F₂ at low x and diffractive production within a Generalized Vector Dominance picture. (author)

[en] We review the basis mechanism of radiative corrections to deeply inelastic electron-proton scattering. (orig.)

[en] I summarize the calculation of O(α_S) corrections to the production of a hard and isolated photon accompanied by one or two jets in deep inelastic lepton nucleon scattering at HERA. (author)

[en] We calculate the complete electromagnetique and weak radiative corrections of O(α³) to neutral current deep inelastic lepoton proton scattering at HERA energies in the framework of the quark parton model. QCD scaling violations in the leading logarithmic approximation are also included. We give predictions for the unpolarized cross section and the polarization and charge asymmetries and discuss the theoretical uncertainties due to the dependence of the radiative corrections on electroweak parameters, quark masses and parton distribution functions. (orig.)

[en] I review theoretical interpretations of the recently observed excess of high-Q² events in deep-inelastic positron-proton scattering at HERA, concentrating on scenarios with leptoquarks or squarks with R-parity violating couplings. (author)