Costly Enforcement of Property Rights and the Coase Theorem

We examine a setting in which property rights are initially ambiguously defined. Whether the parties go to court to remove the ambiguity or bargain and settle privately, they incur enforcement costs. When the parties bargain, a version of the Coase theorem holds. Despite the additional costs of going to court, other ex post ine.ciencies, and the absence of incomplete information, however, going to court may be an equilibrium or ex ante Pareto-superior over settlement; this is especially true in dynamic settings whereby a court decision saves on future enforcement costs. When the parties do not negotiate and go to court the Coase theorem ceases to hold, and a simple rule for the initial assignment of rights maximizes net surplus.

Giant ultrafast Kerr effect in type-II superconductors

We study the ultrafast Kerr effect and high-harmonic generation in type-II superconductors by formulating a new model for a time-varying electromagnetic pulse normally incident on a thin-film superconductor. It is found that type-II superconductors exhibit exceptionally large $\chi^{(3)}$ due to the progressive destruction of Cooper pairs, and display high-harmonic generation at low incident intensities, and the highest nonlinear susceptibility of all known materials in the THz regime. Our theory opens up new avenues for accessible analytical and numerical studies of the ultrafast dynamics of superconductors

On the Topological Nature of the Hawking Temperature of Black Holes

In this work we determine that the Hawking temperature of black holes possesses a purely topological nature. We find a very simple but powerful formula, based on a topological invariant known as the Euler characteristic, which is able to provide the exact Hawking temperature of any two-dimensional black hole -- and in fact of any metric that can be dimensionally reduced to two dimensions -- in any given coordinate system, introducing a covariant way to determine the temperature only using virtually trivial computations. We apply the topological temperature formula to several known black hole systems as well as to the Hawking emission of solitons of integrable equations.Comment: Updated version with more relevant reference

Universal quantum Hawking evaporation of integrable two-dimensional solitons

We show that any soliton solution of an arbitrary two-dimensional integrable equation has the potential to eventually evaporate and emit the exact analogue of Hawking radiation from black holes. From the AKNS matrix formulation of integrability, we show that it is possible to associate a real spacetime metric tensor which defines a curved surface, perceived by the classical and quantum fluctuations propagating on the soliton. By defining proper scalar invariants of the associated Riemannian geometry, and introducing the conformal anomaly, we are able to determine the Hawking temperatures and entropies of the fundamental solitons of the nonlinear Schroedinger, KdV and sine-Gordon equations. The mechanism advanced here is simple, completely universal and can be applied to all integrable equations in two dimensions, and is easily applicable to a large class of black holes of any dimensionality, opening up totally new windows on the quantum mechanics of solitons and their deep connections with black hole physics