Oligopoly and financial structure revisited

In this paper we employ a two stage Cournot duopoly model where firms can obtain outside funds only to finance production plans payouts to shareholders are not allowed. Debt, equity and capacity are chosen in the first stage and output is chosen in the second stage. In contrast to the existing literature in this area, we show firms always choose zero debt in equilibrium. The two important implications of our analysis are (a) while there are linkages between financial structure and product market decisions, these linkages have no real effect on the choice of optimal capital structure of a firm, and (b) the standard results in this area are not robust to model specifications.

Stable, finite energy density solutions in the effective theory of non-abelian gauge fields

We consider the gauge fixed partition function of pure $SU(N_c)$ gauge theory in axial gauge following the Halpern's field strength formalism. We integrate over $3 (N_c^2-1)$ field strengths using the Bianchi identities and obtain an effective action of the remaining $3 (N_c^2-1)$ field strengths in momentum space. We obtain the static solutions of the equations of motion (EOM) of the effective theory. The solutions exhibit Gaussian nature in the $z$ component of momentum and are proportional to the delta functions of the remaining components of momentum. The solutions render a finite energy density of the system and the parameters are found to be proportional to fourth root of the gluon condensate. It indicates that the solutions offer a natural mass scale in the low energy phase of the theory.Comment: 6 pages Minor changes in the manuscript and two figures adde

POMDPs under Probabilistic Semantics

We consider partially observable Markov decision processes (POMDPs) with limit-average payoff, where a reward value in the interval [0,1] is associated to every transition, and the payoff of an infinite path is the long-run average of the rewards. We consider two types of path constraints: (i) quantitative constraint defines the set of paths where the payoff is at least a given threshold lambda_1 in (0,1]; and (ii) qualitative constraint which is a special case of quantitative constraint with lambda_1=1. We consider the computation of the almost-sure winning set, where the controller needs to ensure that the path constraint is satisfied with probability 1. Our main results for qualitative path constraint are as follows: (i) the problem of deciding the existence of a finite-memory controller is EXPTIME-complete; and (ii) the problem of deciding the existence of an infinite-memory controller is undecidable. For quantitative path constraint we show that the problem of deciding the existence of a finite-memory controller is undecidable.Comment: Appears in Proceedings of the Twenty-Ninth Conference on Uncertainty in Artificial Intelligence (UAI2013