Is tourism an opportunity for lagging countries in the elusive quest for growth (Easterly, 2002)? Recent empirical evidence suggests that the answer is a cautious yes. Aggregate cross-country data show that tourism specialization is likely to be associated with higher per capita GDP growth rates...

A stepwise Carnot cycle is performed by means of N small weights (here called dw's), which are first added and then removed from the piston of the vessel containing the gas. The size of the dw's affects the entropy production. The work performed by the gas can be found as increase of the...

We present a mean-field analysis of a fully frustrated Ising spin model on an Ising lattice gas. This is equivalent to a degenerate Blume–Emery–Griffiths model with frustration, which we analyse for different values of the quadrupolar interaction. We find that the regular disorder shifts the...

We use a rigorous, recently developed, method of solution of spin models on Bethe lattices (Cayley trees). It allows us to detect all the phases of the ferromagnetic and antiferromagnetic q-state Potts models in a field (FPM and APM respectively). The phase diagrams of the FPM are characterized...

A rigorous method recently introduced for the solution of spin models on Bethe lattices is used to solve the three-state antiferromagnetic Potts model in an external field, and to find its phase diagram. Critical lines where the system undergoes first-order or second-order phase transitions are...

The AB-correlated-site/random-bond percolation problem in a q-state antiferromagnetic Potts model on Bethe lattices is solved. We find the analytic expression of the AB-percolation characteristic functions in terms of the temperature, the external field and the active bond concentration pB. The...