We characterize optimal debt policy in a dynamic stochastic general equilibrium model of defaults and devaluations in which self-fulfilling crises can arise. When the government cannot commit to repay its debt and cannot commit to maintain the exchange rate, consumers’ expectations of...

We construct a two-sector vintage capital model with neutral and investment-specific technical progress and variable utilization of each vintage. The lifetime of capital goods is endogenous and it relies on the associated maintenance costs. First, we show that the lifetime of capital is an...

The range of applicability of the mean spherical approximation to a primitive-model electrolyte is extended to allow for stronger Coulomb coupling. The new terms in the approximation are extracted from the HNC formalism, which is adequate for strongly coupled Coulomb systems. The new...

A simple polar fluid is modelled by square-well particles with point dipoles and quadrupoles at their centers. An equation for the free energy is derived by perturbation theory, obtaining the explicit dependence on the potential parameters, and allowing to study the effects of the strength of...

We generate exact mixing rules for dilute gaseous mixtures with nonconformal interactions by introducing an adequate effective potential. The general mixing rule leads to several approximations of the van der Waals type. The work uses nonconformal model pair potentials that accurately describe...