ac driven sine-Gordon solitons: dynamics and stability

The ac driven sine-Gordon equation is studied analytically and numerically, with the aim of providing a full description of how soliton solutions behave. To date, there is much controversy about when ac driven dc motion is possible. Our work shows that kink solitons exhibit dc or oscillatory motion depending on the relation between their initial velocity and the force parameters. Such motion is proven to be impossible in the presence of damping terms. For breathers, the force amplitude range for which they exist when dissipation is absent is found. All the analytical results are compared with numerical simulations, which in addition exhibit no dc motion at all for breathers, and an excellent agreement is found. In the conclusion, the generality of our results and connections to others systems for which a similar phenomenology may arise are discussed.Comment: 10 pages, latex, PostScript figures included with epsfig, to appear in European Physical Journal B, see GISC homepage at http://valbuena.fis.ucm.es/ for related wor

Inflation targeting and monetary analysis in Chile and Mexico

This paper studies the role of monetary and open economy indicators in inflation targeting (IT) economies through the analysis of a nested Phillips curve/ P-star model for Chile and Mexico. For Chile a real money gap and a money growth indicator are found to be relevant in predicting deviations of observed from target inflation. In contrast, for Mexico real exchange rate measures are robust predictors of deviations of actual from (i) expected inflation during the pre-IT (1999) period, and (ii) target inflation in the post-IT span.inflation targeting, monetary policy, money demand, PPP, P-star, Phillips curve, cointegration, Kalman filter, block Granger non-causality, VARs