1,057 research outputs found

    Die Entwicklung des russischen DemokratieverstÀndnisses 2008-2012: Gab es einen demokratischen Aufbruch?

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    Aufgrund der ĂŒberraschend ausgebrochenen grĂ¶ĂŸten Demonstrationen der Wladimir Putin-Ära, welche einen Protest gegen die weitgehend als Betrug wahrgenommenen Duma-Wahlen vom Dezember 2011 darstellten, spekulierten viele Beobachter, dass es in Russland zu einem demokratischen Aufbruch kommen könnte. Ein Vergleich der unmittelbar nach den Parlaments- und PrĂ€sidentschaftswahlen in den Jahren 2008 und 2012 in Russland durchgefĂŒhrten Meinungsumfragen offenbart jedoch nur wenige Anzeichen eines solchen Aufbruchs und zeigt, dass die UnterstĂŒtzung fĂŒr die Demokratie gleich geblieben ist. Die Meinungsumfragen zeigen auch, dass die Idee des "Aufbruchs" unpassend sein könnte, weil die "Demokratie", die von vielen Russen unterstĂŒtzt wird, gleichzeitig mit einem "starken AnfĂŒhrer" vereinbar ist, der ohne "Checks and Balances" herrscht. Sie unterstĂŒtzen das, was Guillermo O'Donnell bekanntermaßen eine "delegative Demokratie" nannte, in der die Menschen frei und regelmĂ€ĂŸig StaatsoberhĂ€upter wĂ€hlen, von welchen dann erwartet wird, dass sie ihre breite Macht ohne EinschrĂ€nkungen ausĂŒben, um Probleme zu lösen und Weiterentwicklung zu fördern

    Rotation periods of exoplanet host stars

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    The stellar rotation periods of ten exoplanet host stars have been determined using newly analysed Ca II H & K flux records from Mount Wilson Observatory and Stromgren b, y photometric measurements from Tennessee State University's automatic photometric telescopes (APTs) at Fairborn Observatory. Five of the rotation periods have not previously been reported, with that of HD 130322 very strongly detected at Prot = 26.1 \pm 3.5 d. The rotation periods of five other stars have been updated using new data. We use the rotation periods to derive the line-of-sight inclinations of the stellar rotation axes, which may be used to probe theories of planet formation and evolution when combined with the planetary orbital inclination found from other methods. Finally, we estimate the masses of fourteen exoplanets under the assumption that the stellar rotation axis is aligned with the orbital axis. We calculate the mass of HD 92788 b (28 MJ) to be within the low-mass brown dwarf regime and suggest that this object warrants further investigation to confirm its true nature.Comment: Accepted for publication in MNRAS. 15 pages, 11 figure

    Report of the Astronomy Committee

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    The present report relates only to the scientific needs of Astronomy. Its applications to the possible services that astronomers can render in the war, as a part of the work done by the National Research Council in connection with the Council of National Defense, will be made the subject of a separate study

    A striking correspondence between the dynamics generated by the vector fields and by the scalar parabolic equations

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    The purpose of this paper is to enhance a correspondence between the dynamics of the differential equations y˙(t)=g(y(t))\dot y(t)=g(y(t)) on Rd\mathbb{R}^d and those of the parabolic equations u˙=Δu+f(x,u,∇u)\dot u=\Delta u +f(x,u,\nabla u) on a bounded domain Ω\Omega. We give details on the similarities of these dynamics in the cases d=1d=1, d=2d=2 and d≄3d\geq 3 and in the corresponding cases Ω=(0,1)\Omega=(0,1), Ω=T1\Omega=\mathbb{T}^1 and dim(Ω\Omega)≄2\geq 2 respectively. In addition to the beauty of such a correspondence, this could serve as a guideline for future research on the dynamics of parabolic equations

    The resistive state in a superconducting wire: Bifurcation from the normal state

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    We study formally and rigorously the bifurcation to steady and time-periodic states in a model for a thin superconducting wire in the presence of an imposed current. Exploiting the PT-symmetry of the equations at both the linearized and nonlinear levels, and taking advantage of the collision of real eigenvalues leading to complex spectrum, we obtain explicit asymptotic formulas for the stationary solutions, for the amplitude and period of the bifurcating periodic solutions and for the location of their zeros or "phase slip centers" as they are known in the physics literature. In so doing, we construct a center manifold for the flow and give a complete description of the associated finite-dimensional dynamics

    Instability of the steady states of some Ginzburg–Landau-like equations with real coefficients

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    The instability of the steady states with nonconstant amplitude is analysed for a nonlocal Ginzburg–Landau equation with real coefficients and quasiperiodic boundary conditions. The results are obtained in terms of easily recognized, qualitative properties of the steady states. Some of the results are new, even for the standard (local) Ginzburg–Landau equation with real coefficients. A related Ginzburg–Landau equation coupled to a mean field is also considered that appears in the analyses of counter-propagating waves in extended systems, nonoscillatory instabilities with a conservation law, and viscous Faraday waves in large aspect ratio containers
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