Perturbative unitarity of Lee-Wick quantum field theory

Understand

We study the perturbative unitarity of the Lee-Wick models, formulated as nonanalytically Wick rotated Euclidean theories.

• The complex energy plane is divided into disconnected regions and the values of a loop integral in the various regions are related to one another by a nonanalytic procedure.
• We show that the one-loop diagrams satisfy the expected, unitary cutting equations in each region: only the physical degrees of freedom propagate through the cuts.
• The goal can be achieved by working in suitable subsets of each region and proving that the cutting equations can be analytically continued as a whole.