Voluntary Participation in a Mechanism Implementing a Public Project

In this study, a participation game in a mechanism to implement a public project is considered; in this game, agents decide simultaneously whether they will participate in the mechanism or not. We characterize the sets of participants at strict Nash equilibria, strong equilibria, and coalition-proof equilibria of the participation game. The three sets of equilibria are shown to coincide and exist. All the equilibrium allocations are Pareto efficient at any one of three notions of equilibria. However, if the public good can be provided in multiple units or if there are multiple projects, then these sets may fail to coincide.Participation game, Public project, Strong equilibrium, Coalition-proof equilibrium, Multi-unit public good, Multiple projects

BRST Invariance of the Non-Perturbative Vacuum in Bosonic Open String Field Theory

Tachyon condensation on a bosonic D-brane was recently demonstrated numerically in Witten's open string field theory with level truncation approximation. This non-perturbative vacuum, which is obtained by solving the equation of motion, has to satisfy furthermore the requirement of BRST invariance. This is indispensable in order for the theory around the non-perturbative vacuum to be consistent. We carry out the numerical analysis of the BRST invariance of the solution and find that it holds to a good accuracy. We also mention the zero-norm property of the solution. The observations in this paper are expected to give clues to the analytic expression of the vacuum solution.Comment: 14 pages, no figures, LaTeX2e, v2: references added, minor changes, v3: typos correcte

Sintered silicon nitride workpiece

A description is given of a sintering method for silicon nitride. A detailed explanation of the invention is presented. Four procedures for the sintering process are described

Indicators of Reconnection Processes and Transition to Global Chaos in Nontwist Maps

Reconnection processes of twin-chains are systematically studied in the quadratic twist map. By using the reversibility and symmetry of the mapping, the location of the indicator points is theoretically determined in the phase space. The indicator points enable us to obtain useful information about the reconnection processes and the transition to global chaos. We succeed in deriving the general conditions for the reconnection thresholds. In addition, a new type of reconnection process which generates shearless curves is studied.Comment: 10 pages, 10 GIF figures, to appear in Prog. Theor. Phys. 100 (1998