Linear Solar Models: a simple tool to investigate the properties of solar interior

We describe a simple method to study the dependence of the solar properties on a generic (small) modification the physical inputs adopted in standard solar models calculations.Comment: 3 pages, proceeding of the TAUP09 Worksho

Monte-Carlo simulations of the violation of the fluctuation-dissipation theorem in domain growth processes

Numerical simulations of various domain growth systems are reported, in order to compute the parameter describing the violation of fluctuation dissipation theorem (FDT) in aging phenomena. We compute two-times correlation and response functions and find that, as expected from the exact solution of a certain mean-field model (equivalent to the O(N) model in three dimensions, in the limit of N going to infinity), this parameter is equal to one (no violation of FDT) in the quasi-equilibrium regime (short separation of times), and zero in the aging regime.Comment: 5 pages, 5 eps figure

Effective temperature of a dissipative driven mesoscopic system

We study the nonequilibrium dynamics of a mesoscopic metallic ring threaded by a time-dependent magnetic field and coupled to an electronic reservoir. We analyze the relation between the (non-stationary) real-time Keldysh and retarded Green functions and we find that, in the linear response regime with weak heat transfer to the environment, an effective temperature accounts for the modification of the equilibrium fluctuation-dissipation relation. We discuss possible extensions of this analysis.Comment: 4 pages, 4 figures, RevTe

Direct measurement of the quantum state of the electromagnetic field in a superconducting transmission line

We propose an experimental procedure to directly measure the state of an electromagnetic field inside a resonator, corresponding to a superconducting transmission line, coupled to a Cooper-pair box (CPB). The measurement protocol is based on the use of a dispersive interaction between the field and the CPB, and the coupling to an external classical field that is tuned to resonance with either the field or the CPB. We present a numerical simulation that demonstrates the feasibility of this protocol, which is within reach of present technology.Comment: Accepted for publication in Physical Review A (Rapid Communication). 4 pages, 2 figure