We investigate whether income inequality affects subsequent growth in a cross-country sample for 1965-90, using the models of Barro (1997), Bleaney and Nishiyama (2002) and Sachs and Warner (1997), with negative results. We then investigate the evolution of income inequality over the same period and its correlation with growth. The dominating feature is inequality convergence across countries. This convergence has been significantly faster amongst developed countries. Growth does not appear to influence the evolution of inequality over time. Outline

https://www.econstor.eu/bitstream/10419/81822/1/02-28.pdf

Economic growth and income inequality

This essay elaborates a critical geographical perspective on neoliberalism that emphasizes (a) the path–dependent character of neoliberal reform projects and (b) the strategic role of cities in the contemporary remaking of political–economic space. We begin by presenting the methodological foundations for an approach to the geographies of what we term “actually existing neoliberalism.” In contrast to neoliberal ideology, in which market forces are assumed to operate according to immutable laws no matter where they are “unleashed,” we emphasize the contextual embeddedness of neoliberal restructuring projects insofar as they have been produced within national, regional, and local contexts defined by the legacies of inherited institutional frameworks, policy regimes, regulatory practices, and political struggles. An adequate understanding of actually existing neoliberalism must therefore explore the path–dependent, contextually specific interactions between inherited regulatory landscapes and emergent neoliberal, market–oriented restructuring projects at a broad range of geographical scales. These considerations lead to a conceptualization of contemporary neoliberalization processes as catalysts and expressions of an ongoing creative destruction of political–economic space at multiple geographical scales. While the neoliberal restructuring projects of the last two decades have not established a coherent basis for sustainable capitalist growth, it can be argued that they have nonetheless profoundly reworked the institutional infrastructures upon which Fordist–Keynesian capitalism was grounded. The concept of creative destruction is presented as a useful means for describing the geographically uneven, socially regressive, and politically volatile trajectories of institutional/spatial change that have been crystallizing under these conditions. The essay concludes by discussing the role of urban spaces within the contradictory and chronically unstable geographies of actually existing neoliberalism. Throughout the advanced capitalist world, we suggest, cities have become strategically crucial geographical arenas in which a variety of neoliberal initiatives—along with closely intertwined strategies of crisis displacement and crisis management—have been articulated.

/pdf/cities-and-the-geographies-of-actually-existing-3vwu5dpsnq.pdf

Cities and the Geographies of “Actually Existing Neoliberalism”

Although fundamental for astrophysics, the processes that produce massive stars are not well understood. Large distances, high extinction, and short timescales of critical evolutionary phases make observations of these processes challenging. Lacking good observational guidance, theoretical models have remained controversial. This review offers a basic description of the collapse of a massive molecular core and a critical discussion of the three competing concepts of massive star formation: ▪  monolithic collapse in isolated cores ▪  competitive accretion in a protocluster environment ▪  stellar collisions and mergers in very dense systems We also review the observed outflows, multiplicity, and clustering properties of massive stars, the upper initial mass function and the upper mass limit. We conclude that high-mass star formation is not merely a scaled-up version of low-mass star formation with higher accretion rates, but partly a mechanism of its own, primarily owing to the role of stellar mass ...

Toward Understanding Massive Star Formation

Data Reduction And Error Analysis For The Physical Sciences

Handbook of the Economics of Finance

We present here the final results of the first spectropolarimetric survey of a small sample of active M dwarfs, aimed at providing observational constraints on dynamo action on both sides of the full-convection threshold (spectral type M4). Our two previous studies (Donati et al. 2008b; Morin et al. 2008b) were focused on early and mid M dwarfs. The present paper examines 11 fully convective late M dwarfs (spectral types M5–M8). Tomographic imaging techniques were applied to time-series of circularly polarised profiles of 6 stars, in order to infer their large-scale magnetic topologies. For 3 other stars we could not produce such magnetic maps, because of low variability of the Stokes V signatures, but were able to derive some properties of the magnetic fields. We find 2 distinct categories of magnetic topologies: on the one hand strong axisymmetric dipolar fields (similar to mid M dwarfs), and on the other hand weak fields generally featuring a significant non-axisymmetric component, and sometimes a significant toroidal one. Comparison with unsigned magnetic fluxes demonstrates that the second category of magnetic fields shows less organization (less energy in the large scales), similarly to partly convective early M dwarfs. Stars in both categories have similar stellar parameters, our data do not evidence a separation between these 2 categories in the mass-rotation plane. We also report marginal detection of a large-scale magnetic field on the M8 star VB 10 featuring a significant toroidal axisymmetric component, whereas no field is detectable on VB 8 (M7).

Large-scale magnetic topologies of late M dwarfs★: Magnetic topologies of late M dwarfs

We report the discovery of a medium-strength (~0.5kG) magnetic field on the young, massive star tauSco (B0.2V), which becomes the third-hottest magnetic star known. Circularly polarized Zeeman signatures are clearly detected in observations collected mostly with the ESPaDOnS spectropolarimeter, recently installed on the 3.6-m Canada-France-Hawaii Telescope; temporal variability is also clearly established in the polarimetry, and can be unambiguously attributed to rotational modulation with a period close to 41d. Archival UV spectra confirm that this modulation repeats over timescales of decades. 
By reconstructing the large-scale structure of its magnetic topology, we find that the magnetic structure is unusually complex for a hot star. The surface topology is dominated by a potential field, although a moderate toroidal component is probably present. We fail to detect intrinsic temporal variability of the magnetic structure over the 1.5-yr period of our spectropolarimetric observations (in agreement with the stable temporal variations of the UV spectra), and infer that any differential surface rotation must be very small. 
The topology of the extended magnetic field that we derive from the photospheric magnetic maps is also more complex than a global dipole, and features in particular a significantly warped torus of closed magnetic loops encircling the star (tilted at about 90deg to the rotation axis), with additional, smaller, networks of closed field lines. This topology appears to be consistent with the exceptional Xray properties of tauSco and also provides a natural explanation of the variability observed in wind-formed UV lines. We conclude that its magnetic field is most probably a fossil remnant from the star-formation stage.

The surprising magnetic topology of tauSco: fossil remnant or dynamo output?

We report in this paper phase-resolved spectropolarimetric observations of the rapidly-rotating fully-convective M4 dwarf V374 Peg, on which a strong, mainly axisymmetric, large-scale poloidal magnetic field was recently detected. In addition to the original data set secured in 2005 August, we present here new data collected in 2005 September and 2006 August. From the rotational modulation of unpolarised line profiles, we conclude that starspots are present at the surface of the star, but their contrast and fractional coverage are much lower than those of non-fully convective active stars with similar rotation rate. Applying tomographic imaging on each set of circularly polarised profiles separately, we find that the large-scale magnetic topology is remarkably stable on a timescale of 1 yr; repeating the analysis on the complete data set suggests that the magnetic configuration is sheared by very weak differential rotation (about 1/10th of the solar surface shear) and only slightly distorted by intrinsic variability. This result is at odds with various theoretical predictions, suggesting that dynamo fields of fully-convective stars should be mostly non-axisymmetric unless they succeed at triggering significant differential rotation.

The stable magnetic field of the fullly-convective star V374 Peg

From observations made with the ESPaDOnS spectropolarimeter, recently installed on the 3.6-m Canada--France--Hawaii Telescope, we report the discovery of a strong magnetic field in the Of?p spectrum variable HD 191612 -- only the second known magnetic O star (following theta1 Ori C). The stability of the observed Zeeman signature over four nights of observation, together with the non-rotational shape of line profiles, argue that the rotation period of HD 191612 is significantly longer than the 9-d value previously proposed. We suggest that the recently identified 538-d spectral-variability period is the rotation period, in which case the observed line-of-sight magnetic field of -220+-38 G implies a large-scale field (assumed dipolar) with a polar strength of about -1.5 kG. If confirmed, this scenario suggests that HD 191612 is, essentially, an evolved version of the near-ZAMS magnetic O star theta1 Ori C, but with an even stronger field (about 15 kG at an age similar to that of theta1Ori C). We suggest that the rotation rate of HD 191612, which is exceptionally slow by accepted O-star standards, could be due to angular-momentum dissipation through a magnetically confined wind.

Discovery of a strong magnetic field on the O star HD 191612: new clues to the future of theta1 Orionis C?

PolarBase is an evolving database that contains all stellar data collected with the ESPaDOnS and NARVAL high-resolution spectropolarimeters, in their reduced form, as soon as they become public. As of early 2014, observations of 2000 stellar objects throughout the Hertzsprung-Russell diagram are available. Intensity spectra are available for all targets, and the majority of the observations also include simultaneous spectra in circular or linear polarization, with the majority of the polarimetric measurements being performed only in circularly polarized light (Stokes V). Observations are associated with a cross-correlation pseudoline profile in all available Stokes parameters, greatly increasing the detectability of weak polarized signatures. Stokes V signatures are detected for more than 300 stars of all masses and evolutionary stages, and linear polarization is detected in 35 targets. The detection rate in Stokes V is found to be anticorrelated with the stellar effective temperature. This unique set of Zeeman detections offers the first opportunity to run homogeneous magnetometry studies throughout the H-R diagram. The Web interface of PolarBase is available at http://polarbase.irap.omp.eu.

https://www.jstor.org/stable/10.1086/676976

Pascal Petit

Papers

Large-scale magnetic topologies of late M dwarfs★: Magnetic topologies of late M dwarfs

The surprising magnetic topology of tauSco: fossil remnant or dynamo output?

The stable magnetic field of the fullly-convective star V374 Peg

Discovery of a strong magnetic field on the O star HD 191612: new clues to the future of theta1 Orionis C?

PolarBase: A Database of High-Resolution Spectropolarimetric Stellar Observations