Effective energy-momentum tensor for a vector collective mode

Abstract

The energy-momentum tensor for the self-coupled charged boson model ${({\ensuremath{\phi}}^{*}{\overline{\ensuremath{\partial}}}_{\ensuremath{\mu}}\ensuremath{\phi})}^{2}$ exhibiting collective phenomena is studied within the Hartree approximation. The singular part of the Callan-Coleman-Jackiw improved tensor for the model induces an effective energy-momentum tensor, which is symmetric and conformal, for the vector collective mode. The Bjorken model (self-interacting fermion theory with the vector coupling) is also discussed.