Particle creation using the classical stochastic method

We compute the particle creation of a harmonic oscillator using the classical stochastic method. This method reproduces all the vacuum expectation values in quantum theory. We prepare the vacuum state at the initial time and evolve it over time using Langevin equations of motion. By averaging over the ensemble, we compute the energy of the state at the final time and determine the amount of particles created. We verify that the particle creation agrees with predictions from quantum theory.