Abstract

In IQFT, a standard approach to compute correlation functions is the form factor bootstrap. The form factors satisfy some axioms, which can help us solve the form factors. Recently, this approach was used in TTbar-deformed IQFT by considering the CDD factor deformation. Through the well-known “replica-trick”, we solve the form factor bootstrap axioms for the branch-point twist fields and obtain the deformed twist fields form factors. Using these deformed form factors, we compute the deformed entanglement entropy in TTbar deformed IQFT up to two particle contributions. We find that the UV behavior of the entanglement entropy is changed drastically.