Does a Single Zealot Affect an Infinite Group of Voters ?

A method for studying exact properties of a class of {\it inhomogeneous} stochastic many-body systems is developed and presented in the framework of a voter model perturbed by the presence of a ``zealot'', an individual allowed to favour an opinion. We compute exactly the magnetization of this model and find that in one (1d) and two dimensions (2d) it evolves, algebraically ($\sim t^{-1/2}$) in 1d and much slower ($\sim 1/\ln{t}$) in 2d, towards the unanimity state chosen by the zealot. In higher dimensions the stationary magnetization is no longer uniform: the zealot cannot influence all the individuals. Implications to other physical problems are also pointed out.Comment: 4 pages, 2-column revtex4 forma

The software for the robotization of the TROBAR telescope

The Telescopi ROBotic de ARas (TROBAR) is a new robotic facility built at Aras de Los Olmos (Valencia-Spain). This is a 60cm telescope equipped with a 4kx4k optical camera, corresponding to 30x30 arcmin2 FoV, and it will be primarily used for a systematic search of Ha emitting stars in the Galactic Plane to a depth of ~14mag. Both data acquisition and reduction will be performed automatically. The robotization of data acquisition is now entering its final phase while the development of the data reduction pipeline has just started.Comment: 10 pages, 3 figures. Accepted for publication in Advances in Astronomy - Robotic Astronomy special issu

Local automorphisms of finite dimensional simple Lie algebras

Let ${\mathfrak g}$ be a finite dimensional simple Lie algebra over an algebraically closed field $K$ of characteristic $0$. A linear map $\varphi:{\mathfrak g}\to {\mathfrak g}$ is called a local automorphism if for every $x$ in ${\mathfrak g}$ there is an automorphism $\varphi_x$ of ${\mathfrak g}$ such that $\varphi(x)=\varphi_x(x)$. We prove that a linear map $\varphi:{\mathfrak g}\to {\mathfrak g}$ is local automorphism if and only if it is an automorphism or an anti-automorphism.Comment: 14 page

An elementary proof of the uniqueness of the solutions of linear odes

In this note, we present an elementary proof of the uniqueness of the solutions of the initial value problems of linear ordinary differential equations (odes)