From spin chains to real-time thermal field theory using tensor networks

Abstract: One of the most interesting directions in theoretical high-energy and condensed-matter physics is understanding dynamical properties of collective states of quantum field theories. The most elementary tool in this quest is retarded equilibrium correlators governing the linear response theory. In this talk, I will describe how tensor networks can be used to determine retarded correlators in an ab initio way for a class of (1 + 1)-dimensional quantum field theories that arise as infrared descriptions of quantum Ising chains. I will show that, complemented with signal analysis using the Prony method, tensor network calculations for intermediate times provide a powerful way to explore the structure of singularities of the correlator in the complex frequency plane and to make predictions about the thermal response to perturbations in a class of nonintegrable interacting quantum field theories. The talk is based on arXiv:1912.08836. Time permitting, I will also mention some follow-up directions emerging from this line of research.

statistical mechanicsHEP - theorycomputational physicsquantum physics

Audience: researchers in the topic

HEP-tensor network seminars

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