# Antiferromagnetic 4-d O(4) Model

## TL;DR

This paper investigates the phase diagram of the four-dimensional O(4) model with specific neighbor couplings, identifying a second-order transition line and calculating critical exponents that differ from mean-field predictions.

## Contribution

It provides new insights into the phase structure of the 4D O(4) model, especially in the beta2 < 0 region, and computes critical exponents using finite size scaling.

## Key findings

- Identified a second-order transition line in the phase diagram.
- Computed critical exponents that differ from mean-field values.
- Analyzed the model at the F4 lattice point with lattice sizes up to 24.

## Abstract

We study the phase diagram of the four dimensional O(4) model with first (beta1) and second (beta2) neighbor couplings, specially in the beta2 < 0 region, where we find a line of transitions which seems to be second order. We also compute the critical exponents on this line at the point beta1 =0 (F4 lattice) by Finite Size Scaling techniques up to a lattice size of 24, being these exponents different from the Mean Field ones.