Discontinuous phase transition in an open-ended Naming Game

In this work we study on a 2D square lattice a recent version of the Naming Game, an agent-based model used for describing the emergence of linguistic structures. The system is open-ended and agents can invent new words throughout the evolution of the game, picking them up from a pool characterised by a Gaussian distribution with standard deviation σ . The model displays a nonequilibrium phase transition at a critical point σ c ≈ 25.6, which separates an absorbing consensus state from an active fragmented state where agents continuously exchange different words. The finite-size scaling analysis of our simulations strongly suggests that the phase transition is discontinuous.