High precision calculations in quantum field theory

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The following decade is crucial for our understanding of the fundamental structure of elementary particles and forces. Large Hadron Collider (LHC) is already collecting data which will give access to a completely new energy domain and could in a nearest future uncover principally new phenomena such as the extra space dimensions, supersymmetry, etc. On the other hand increasing accuracy of the low-energy experiments makes possible a very accurate determination of the fundamental parameters of the standard model of particle interactions and becomes competitive in probing new physics beyond the standard model. In most cases the new physics shows up as a tiny deviation from the theoretical predictions based on the standard model. Thus the high precision of the predictions becomes mandatory. The main goal of the project is the calculation of the high order perturbative corrections in a wide class of the quantum field theory problems ranging from nonrelativistic threshold to ultrarelativistic Sudakov limit, which are of primary phenomenological importance for current and future experiments. This includes in particular the electroweak radiative corrections to the electron-positron scattering, which is the ``standard candle'' for electron-positron colliders, the strong coupling radiative corrections to the top-antitop threshold production and to the properties of the bottomonium states, high order analysis of quarkonium and positronium hyperfine splitting. Possible phenomenological applications of the results include precise determination of the heavy quark masses and strong coupling constant. The difficulty of the problems requires developing new theoretical and computational tools which are closely related to the fundamental concepts of the quantum field theory such as the effective field theory approach, renormalization group, etc. Deeper understanding and development of these concepts and possible application of the field theory methods in condensed matter physics are also among the goals of the project.