Topological defects (kinks) in a relativistic $ϕ^{4}$ scalar field theory in $D=(1+1)$ are studied using the matrix product state tensor network. The one kink state is approximated as a matrix product state and the kink mass is calculated. The approach used is quite general and can be applied to a variety of theories and tensor networks. Additionally, the contribution of kink-antikink excitations to the ground state is examined and a general method to estimate the scalar mass from equal time ground state observables is provided. The scalar and kink mass are compared at strong coupling and behave as expected from universality arguments. This suggests that the matrix product state can adequately capture the physics of defect-antidefect excitations and thus provides a promising technique to study challenging non-equilibrium physics such as the Kibble-Zurek mechanism of defect formation.
Lattice Topological Defects in Non-Unitary Conformal Field Theories
Rutgers University（罗格斯大学）；Universidade Federal de São Carlos（圣卡洛斯联邦大学）；Institut de physique théorique, CEA, CNRS, Université Paris-Saclay（巴黎萨克雷大学CEA-CNRS理论物理研究所）；University of Southern California（南加州大学）
