Equilibrium in secure strategies

A new concept of equilibrium in secure strategies (EinSS) in non-cooperative games is presented. The EinSS coincides with the Nash-Cournot Equilibrium when Nash-Cournot Equilibrium exists and postulates the incentive of players to maximize their profit under the condition of security against actions of other players. The new concept is illustrated by a number of matrix game examples and compared with other closely related theoretical models. We prove the existence of equilibrium in secure strategies in four classic games that fail to have Nash-Cournot equilibria. On an infinite line we obtain the solution in secure strategies of the classic Hotelling’s price game (1929) with a restricted reservation price and linear transportation costs. New type of monopolistic solution in secure strategies is discovered in the Tullock Contest (1967, 1980) of two players. For the model of insurance market we prove that the contract pair found by Rothschild, Stiglitz and Wilson (1976) is always an equilibrium in secure strategies. We characterize all equilibria in secure prices in the Bertrand-Edgeworth duopoly model with capacity constraints

Self-energy embedding theory (SEET) for periodic systems

We present an implementation of the self-energy embedding theory (SEET) for periodic systems and provide a fully self-consistent embedding solution for a simple realistic periodic problem - 1D crystalline hydrogen - that displays many of the features present in complex real materials. For this system, we observe a remarkable agreement between our finite temperature periodic implementation results and well established and accurate zero temperature auxiliary quantum Monte Carlo data extrapolated to thermodynamic limit. We discuss differences and similarities with other Green's function embedding methods and provide the detailed algorithmic steps crucial for highly accurate and reproducible results