Speaker
Description
The existence of genuine complex conjugated poles in the gluon propagator is discussed together with the problems that the complex poles would raise.
In the first part, some arguments in favour of their existence are presented. Their appearance in different approaches is reviewed and some features of the complex poles are related to confinement, string tension and condensates.
In the second part, some of the problems raised by the complex-conjugated poles are examined. Notably, the standard Wick rotation and the Kallén-Lehmann representation would be invalidated, thus questioning the physical meaning of the theory and even casting doubts on the existence of a meaningful theory in Minkowski space. A speculative way to solve the main problems is proposed, yielding a modified spectral representation and a relation between the complex poles and the physical spectrum.
