Damping-Antidamping Effect on Comets Motion

We make an observation about Galilean transformation on a 1-D mass variable systems which leads us to the right way to deal with mass variable systems. Then using this observation, we study two-bodies gravitational problem where the mass of one of the bodies varies and suffers a damping-antidamping effect due to star wind during its motion. For this system, a constant of motion, a Lagrangian and a Hamiltonian are given for the radial motion, and the period of the body is studied using the constant of motion of the system. Our theoretical results are applied to Halley's comet.Comment: 19 pages, 5 figures. arXiv admin note: substantial text overlap with arXiv:0910.468

Fluctuations of K-band galaxy counts

We measure the variance in the distribution of off-plane (|b|>20 deg.) galaxies with m_K<13.5 from the 2MASS K-band survey in circles of diameter between 0.344 deg. and 57.2 deg. The use of a near-infrared survey makes negligible the contribution of Galactic extinction to these fluctuations. We calculate these variances within the standard Lambda-CDM model assuming that the sources are distributed like halos of the corresponding mass, and it reproduces qualitatively the galaxy counts variance. Therefore, we test that the counts can be basically explained in terms only of the large scale structure. A second result of this paper is a new method to determine the two point correlation function obtained by forcing agreement between model and data. This method does not need the knowledge of the two-point angular correlation function, allows an estimation of the errors (which are low with this method), and can be used even with incomplete surveys. Using this method we get xi(z=0, r<10 h^{-1}Mpc)=(29.8+/-0.3) (r/h^{-1}Mpc)^{-1.79+/-0.02}, which is the first measure of the amplitude of xi in the local Universe for the K-band. It is more or less in agreement with those obtained through red optical filters selected samples, but it is larger than the amplitude obtained for blue optical filters selected samples.Comment: 7 pages, 5 figures, accepted to be published in A&

Trade and the Environment

Trade, the exchange of goods and services across countries, is often viewed as an engine of economic growth. Benefits of liberalized trade include access to a larger variety of goods and services to consumers, easier access to foreign technologies, access to larger markets for producers, and increased efficiency in resource allocation. The impact of trade on the environment, however, is a contentious issue; air and water pollution, the degradation of natural habitats and loss of species, and global pollutants, particularly carbon dioxide emissions, are major concerns.Environmental Economics and Policy, International Relations/Trade,

When Government Spending Serves the Elites: Consequences for Economic Growth in a Context of Market Imperfections

Government spending should be regarded as a social and political phenomenon, not merely as a technical choice. We argue that there is an implicit contract between the organized elites and politicians which often leads to a pro-elite allocation of public resources. A natural and simple taxonomy of government spending follows from this view: spending in public goods broadly defined which mitigate market failures versus spending in non-social subsidies, mainly a vehicle to serve the elites. We theoretically and empirically show that pro-elite spending biases are costly in terms of economic growth. The empirical findings are exceptionally robust.government spending, economic growth, market imperfections, investment, subsidies, International Development, Labor and Human Capital, Political Economy, Public Economics,