Explicit equilibria in a kinetic model of gambling

A nonlinear kinetic equation of Boltzmann type which describes the evolution of wealth in a pure gambling process is introduced and discussed. In this process the entire sum of wealths of two agents is up for gambling, and randomly shared between the agents. The analytical form of the steady states is found for various realizations of the random fraction of the sum which is shared to the agents. Among others, the exponential distribution appears as steady state in case of a uniformly distributed random fraction, while Gamma distribution appears for a random fraction which is Beta distributed. The case in which the gambling game is only conservative-in-the-mean is shown to lead to an explicit heavy tailed distribution.