Large Scale Structure Formation of Normal Branch in DGP Brane World Model

In this paper, we study the large scale structure formation of the normal branch in DGP model (Dvail, Gabadadze and Porrati brane world model) by applying the scaling method developed by Sawicki, Song and Hu for solving the coupled perturbed equations of motion of on-brane and off-brane. There is detectable departure of perturbed gravitational potential from LCDM even at the minimal deviation of the effective equation of state w_eff below -1. The modified perturbed gravitational potential weakens the integrated Sachs-Wolfe effect which is strengthened in the self-accelerating branch DGP model. Additionally, we discuss the validity of the scaling solution in the de Sitter limit at late times.Comment: 6 pages, 2 figure

Analytic approximations, perturbation theory, effective field theory methods and their applications

We summarize the parallel session B4: 'Analytic approximations, perturbation theory effective field theory methods and their applications' and the joint session B2/B4: 'Approximate solutions to Einstein equations: Methods and Applications', of the GR20 & Amaldi10 conference in Warsaw, July 2013. The contributed talks reported significant advances on various areas of research in gravity.Comment: 15 pages. Contribution to the Proceedings of GR20 - Amaldi1

Natural Supergravity Inflation

We show that a single uncharged chiral superfield, canonically coupled to \mbox{$N=1$} supergravity with vanishing superpotential, naturally drives inflation in the early universe for a class of simple Kahler potentials. Inflation occurs due to the one-loop generation of a Kahler anomaly proportional to $\R^2$. The coefficient of this $\R^2$ term is of the correct magnitude to describe all aspects of an inflationary cosmology, including sufficient amplitude perturbations and reheating. Higher order terms proportional to $\R^n$ for $n \geq 3$ are naturally suppressed relative to the $\R^2$ term and, hence, do not destabilize the theory.Comment: 13 pages, CERN-TH.6685/92, UPR-0526

Brazil's Tropical Plan

This paper highlights the institutional features of the inflation process and contrasts two stabilization efforts in 1964-66 and in 1986.The inflation process in Brazil is highly institutional. It does not resemble hyperinflations where pricing and wage setting are geared to the exchange rate by the hour, making it possible to stop inflation by simply containing money creation and fixing the exchange rate. The two stabilization programs demonstrate that an incomes policy is an essential ingredient to non-recessionary stabilization. But they also show that demand restraint is inevitable if disinflation is to be viable. The 1964 program was gradualist and two-handed, relying on the supply side on wage repression. The 1986 plan was a heterodox shock treatment centered around an uncompromising price freeze and paying insufficient attention to the need for fiscal restraint.