TY - GEN

T1 - Synchronization of coupled oscillators is a game

AU - Yin, Huibing

AU - Mehta, Prashant G.

AU - Meyn, Sean P.

AU - Shanbhag, Uday V.

PY - 2010/10/15

Y1 - 2010/10/15

N2 - The purpose of this paper is to understand phase transition in noncooperative dynamic games with a large number of agents. Applications are found in neuroscience, biology, economics, as well as traditional engineering applications. The focus of analysis is a variation of the large population LQG model of Huang et. al. 2007 [6], comprised here of a controlled nonlinear N-dimensional stochastic differential equation model, coupled only through a nonlinear cost function. The states are interpreted as the phase angle for a collection of non-homogeneous oscillators, and in this way the model may be regarded as an extension of the classical coupled oscillator model of Kuramoto. A deterministic PDE model is proposed, which is shown to approximate the stochastic system as the population size approaches infinity. Key to the analysis of the PDE model is the existence of a particular Nash equilibrium in which the agents 'opt out' of the game, setting their controls to zero, resulting in the 'incoherence' equilibrium. Methods from dynamical systems theory are used in a bifurcation analysis, based on a linearization of the PDE model about the incoherence equilibrium. A critical value of the control cost parameter is identified: Above this value, the oscillators are incoherent; and below this value (when control is sufficiently cheap) the oscillators synchronize. These conclusions are illustrated with results from numerical experiments.

AB - The purpose of this paper is to understand phase transition in noncooperative dynamic games with a large number of agents. Applications are found in neuroscience, biology, economics, as well as traditional engineering applications. The focus of analysis is a variation of the large population LQG model of Huang et. al. 2007 [6], comprised here of a controlled nonlinear N-dimensional stochastic differential equation model, coupled only through a nonlinear cost function. The states are interpreted as the phase angle for a collection of non-homogeneous oscillators, and in this way the model may be regarded as an extension of the classical coupled oscillator model of Kuramoto. A deterministic PDE model is proposed, which is shown to approximate the stochastic system as the population size approaches infinity. Key to the analysis of the PDE model is the existence of a particular Nash equilibrium in which the agents 'opt out' of the game, setting their controls to zero, resulting in the 'incoherence' equilibrium. Methods from dynamical systems theory are used in a bifurcation analysis, based on a linearization of the PDE model about the incoherence equilibrium. A critical value of the control cost parameter is identified: Above this value, the oscillators are incoherent; and below this value (when control is sufficiently cheap) the oscillators synchronize. These conclusions are illustrated with results from numerical experiments.

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M3 - Conference contribution

AN - SCOPUS:77957788593

SN - 9781424474264

T3 - Proceedings of the 2010 American Control Conference, ACC 2010

SP - 1783

EP - 1790

BT - Proceedings of the 2010 American Control Conference, ACC 2010

T2 - 2010 American Control Conference, ACC 2010

Y2 - 30 June 2010 through 2 July 2010

ER -