Speaker
Markus Huber
Description
Contour deformations are a useful tool to perform calculations for complex momenta in Euclidean metric. An application is the calculation of elementary correlations of quarks and gluons. In the case of propagators, it is already used and applied to different cases. However, due to the more complicated kinematics, the situation is different for vertices for which this technique is hardly explored. In this talks, the generalizations necessary for three-point functions are discussed. Contact to the Landau conditions is made which give the positions of branch cuts of integrals. As an example, the emergence of branch cuts in nonperturbative calculations of $\phi^3$ theory is discussed.
Author
Markus Huber
