Construction of the Yukawa2 field theory with a large external field

Abstract

We consider the Yukawa₂ model with (relativistic) interaction density λψ̄Γψφ+μφ, where Γ=1 or γ₅. For sufficiently large μ, we apply the Glimm–Jaffe–Spencer cluster expansion to construct the infinite volume theory satisfying the Wightman and Osterwalder–Schrader axioms including a positive mass gap.