# Entanglement Renormalization for Interacting Field Theories

## TL;DR

This paper introduces a novel non-Gaussian variational approach to entanglement renormalization in interacting quantum field theories, enabling non-perturbative analysis beyond Gaussian approximations.

## Contribution

It develops a scale-dependent nonlinear canonical transformation framework for interacting theories, extending entanglement renormalization beyond free theories with analytical expectation value calculations.

## Key findings

- Successfully applied to $mbda \, ^4$ and sine-Gordon models
- Captures non-perturbative effects beyond Gaussian approximation
- Provides analytical expressions for local operator expectation values

## Abstract

A general method to build the entanglement renormalization (cMERA) for interacting quantum field theories is presented. We improve upon the well-known Gaussian formalism used in free theories through a class of variational non-Gaussian wavefunctionals for which expectation values of local operators can be efficiently calculated analytically and in a closed form. The method consists of a series of scale-dependent nonlinear canonical transformations on the fields of the theory under consideration. Here, the $\lambda\, \phi^4$ and the sine-Gordon scalar theories are used to illustrate how non-perturbative effects far beyond the Gaussian approximation are obtained by considering the energy functional and the correlation functions of the theory.