\documentclass[../ising_model.tex]{subfiles} \begin{document} \begin{abstract} We have studied the ferromagnetic behavior of the Ising model at a critical temperature, when undergoing phase transition. To generate spin configurations, we used the Metropolis-Hastings algorithm, which applies a Markov chain Monte Carlo sampling method. We determined the time of equilibrium to be approximately 3000 Monte Carlo cycles, and used the following samples to find the probability distribution at temperature $T_{1} = 1.0 J / k_{B}$, and $T_{2} = 2.4 J / k_{B}$. For $T_{1}$ the mean energy per spin is $\langle \epsilon \rangle \approx -1.9969 J$, with a variance $\text{Var} (\epsilon) = 0.0001$. And for $T_{2}$, close to the critical temperature, the mean energy per spin is $\langle \epsilon \rangle \approx -1.2370 J$, with a variance $\text{Var} (\epsilon) = 0.0203$. In addition, we estimated the expected energy and magnetization per spin, the heat capacity and magnetic susceptibility. We have estimated the critical temperatures of finite lattice sizes, and used these values to approximate the critical temperature of a lattice of infinite size. Using linear regression, we estimated the critical temperature to be $T_{c}(L = \infty) \approx 2.2695 J/k_{B}$. \end{abstract} \end{document}