From the paper: "it uses a single neural network, rather than separate policy and value networks ... it uses a simpler tree search that relies upon this single

From the paper: "it uses a single neural network, rather than separate policy and value networks ... it uses a simpler tree search that relies upon this single neural network to evaluate positions and sample moves, without performing any MonteCarlo rollouts. To achieve these results, we introduce a new reinforcement learning algorithm that incorporates lookahead search inside the training loop, resulting in rapid improvement and precise and stable learning."