Title: Radiation corrections to atomic spectra. Author: Vojtěch Patkóš Department: Department of chemical physics and optics Supervisor: doc. Mgr. Jaroslav Zamastil, Ph.D., KCHFO Abstract: In present time accuracy of spectroscopic measurements achieved fan- tastic accuracy 1 part in 10 to the power 14. If these measures are followed by theoretical calculations of similar accuracy we can test quantum electrodynamics and part of the standard model responsible for parity violating weak forces by comparing theory and experiment and set some of the basic physical constants like Rydberg constant, mass and radius of nucleus, constant of fine structure and it's variation in time etc. For achieving this kind of accuracy of calculations one must take into account so called radiation corrections. This thesis focus is on accurate calculation of the most important of them, the self-energy of electron in one-loop aproximation. Keywords: Quantum electrodynamics, radiation corrections, self-energy of elec- tron.

In the present thesis we study light-light scattering, which is a nonlinear effect occurring in quantum electrodynamics. The goal of this thesis is to study the low-energy effective theory (Lagrangians of Euler-Heisenberg type). The first part of the work is devoted to the derivation of the effective Lagrangian in spinor, scalar and vector QED using the amplitude matching of one-loop diagrams. The calculation for the case of vector QED is performed using the unitary gauge, which probably has not been done yet so far by other authors. In the second part, the effective Lagrangian for spinor QED is derived using functional methods. The essential point of the derivation is to calculate the determinant of the Dirac operator in constant background electromagnetic field. Powered by TCPDF (www.tcpdf.org)