7 papers
Two-Loop Self-Dual QED
Gerald V. Dunne, Christian Schubert
We present explicit closed-form expressions for the two-loop Euler-Heisenberg Lagrangians in a constant self-dual field, for both spinor and scalar QED. The simplicity of these rep…
Four - Point Functions of Chiral Primary Operators in N=4 SYM
B. Eden, C. Schubert, E. Sokatchev
We discuss recent progress in the determination of correlators of chiral primary operators in N=4 Super-Yang-Mills theory, based on a combination of superconformal covariance argum…
World Line Path Integrals as a Calculational Tool in Quantum Field Theory
Michael G. Schmidt, Christian Schubert
We report on the status of the string-inspired world line path integral formalism, a recently developed powerful tool for the reorganisation of standard perturbative amplitudes in…
On the Calculation of QED Amplitudes in a Constant Field
Christian Schubert
It is explained how first-quantized worldline path integrals can be used as an efficient alternative to Feynman diagrams in the calculation of QED amplitudes and effective actions.…
Multiloop Feynman Integrals in the Worldline Approach
Michael G. Schmidt, Christian Schubert
We explain the concept of worldline Green functions on classes of multiloop graphs. The QED beta function and the 2-loop Euler-Heisenberg Lagrangian are discussed for illustration.
Relativistic QFTH - Couplings on the Worldline
Michael G. Schmidt, Christian Schubert
In the framework of the worldline path integral approach to QFTH we discuss spin and relativistic couplings, in particular Yukawa and axial couplings to spin 1/2, and the case of s…