Human security and the rise of the social

As the concept of human security has become part of the mainstream discourse of international politics it should be no surprise that both realist and critical approaches to international theory have found the agenda wanting. This article seeks to go beyond both the realist and biopolitical critiques by situating all three – political realism, biopolitics and human security – within the history and theory of the modern rise of the social realm from late eighteenth and nineteenth century Europe. Human security is the further expansion of social forms of governance under capitalism, more specifically a form of socialpolitik than realpolitik or biopolitics. Drawing on the work of historical sociologist Robert Castel and political theorist Hannah Arendt, the article develops an alternative framework with which to question the extent to which ‘life’ has become the subject of global intervention through the human security agenda

Solar Response to Luminosity Variations

The connection between solar luminosity and magnetic fields is now well-established. Magnetic fields under the guise of sunspots and faculae enhance or suppress heat transfer through the solar surface, leading to changes in the total solar luminosity. This raises the question of the effect that such surface heat transfer perturbations have on the internal structure of the sun. The problem has been considered previously by Foukal and Spruit. Here, researchers generalize the calculation of Spruit, removing the assumption of a constant heat diffusivity coefficient by treating the full mixing length heat transfer expression. Further, they treat the surface conditions in a simpler manner, and show that the previous conclusions of Foukal and Spruit are unaffected by these modifications. The model shows that following the application of a step function emissivity change: a fraction 1 - D(sub 0) of the luminosity change relaxes away after approx. 50 days. This corresponds to the thermal diffusion time across the convection zone, adjusting to a value in correspondence with the surface change. In other words, the whole convection zone feels the perturbation on this timescale. The remaining fraction relaxes away on a timescale of 10 to the 5th power years, corresponding to the convective layer radiating away enough energy so that it can adjust to its new adiabat. These are the same results arrived at by Spruit and Foukal. For variations of sigma on timescales of 10 to 200 years, then, the only important relaxation is the 50 day one. If the amplitude of this relaxation is small, the luminosity follows the sigma variation

Maximal regularity for non-autonomous Robin boundary conditions

We consider a non-autonomous Cauchy problem involving linear operators associated with time-dependent forms $a(t;.,.):V\times V\to {\mathbb{C}}$ where $V$ and $H$ are Hilbert spaces such that $V$ is continuously embedded in $H$. We prove $H$-maximal regularity under a new regularity condition on the form $a$ with respect to time; namely H{\"o}lder continuity with values in an interpolation space. This result is best suited to treat Robin boundary conditions. The maximal regularity allows one to use fixed point arguments to some non linear parabolic problems with Robin boundary conditions.Comment: 19 pages pour la nouvelle versio

Endogeneity and Heterogeneity in LDV Panel Data Models

We extend three existing cross-sectional limited dependent variable (LDV) estimators, that allow for endogenous regressors, to a panel data model. We focus on estimation of effects of timeinvariant endogenous regressors, since to our knowledge, besides joint maximum likelihood, no other alternative consistent parametric estimators than the ones suggested here exist. We compare their small sample performance of estimates of marginal effects to i.i.d. LDV estimators as well as to linear estimators by means of Monte Carlo Studies. Some notable differences in the performance of the LDV estimators appear. One estimator, the 2SIV, performs reasonably well in terms of bias, even with weak instruments. Another type, the AGLS estimators, have a large small sample bias when no endogeneity is present. The 2SCML estimators seem to perform reasonable in most scenarios even under some types of misspecification. In addition, 2SLS performed relatively well, but had a substantial MSE with weak instruments and substantial bias in misspecified scenarios. Although potentially important because of heterogeneity bias, our extension of LDV models to the panel case did not give improvements in small sample performance over the cross-sectional estimators.Two-Step Estimation; Panel Data; Endogenous Regressor; Time-Invariant Regressor; Linear Approximation