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Race, Rights and Reterritorialization
This Essay considers the possibility of a political and dialectical theory of rights that builds on Critical race and neo-Marxist traditions through revision of formal Marxian approaches and in light of racialized forms of accumulation and anti-systemic struggle. This Essay borrows from the CRT and neo-Marxist traditions in arguing for the centrality of both political contestation and structural economic-materialist conditions in forging a progressive politics of rights. This can be contrasted to a critique of human rights in the international context that sees the discourse itself as depoliticizing insofar as rights become the prime possession of those who are denied a political space in which to assert their claims. The metaphor of rights (re)territorialization captures these concerns, while foregrounding the ongoing importance of race in grounding various aspects of global capital accumulation and concomitant political formations
Is the Multiverse Hypothesis capable of explaining the Fine Tuning of Nature Laws and Constants? The Case of Cellular Automata
The objective of this paper is analyzing to which extent the multiverse
hypothesis provides a real explanation of the peculiarities of the laws and
constants in our universe. First we argue in favor of the thesis that all
multiverses except Tegmark's > are too small to
explain the fine tuning, so that they merely shift the problem up one level.
But the > is surely too large. To prove this
assessment, we have performed a number of experiments with cellular automata of
complex behavior, which can be considered as universes in the mathematical
multiverse. The analogy between what happens in some automata (in particular
Conway's >) and the real world is very strong. But if the
results of our experiments can be extrapolated to our universe, we should
expect to inhabit -- in the context of the multiverse -- a world in which at
least some of the laws and constants of nature should show a certain time
dependence. Actually, the probability of our existence in a world such as ours
would be mathematically equal to zero. In consequence, the results presented in
this paper can be considered as an inkling that the hypothesis of the
multiverse, whatever its type, does not offer an adequate explanation for the
peculiarities of the physical laws in our world. A slightly reduced version of
this paper has been published in the Journal for General Philosophy of Science,
Springer, March 2013, DOI: 10.1007/s10838-013-9215-7.Comment: 30 pages, 16 figures, 5 tables. Slightly reduced version published in
Journal for General Philosophy of Scienc
A Study of Catalogued Nearby Galaxy Clusters in the SDSS-DR4: I. Cluster Global Properties
We have selected a sample of 88 nearby (z<0.1) galaxy clusters from the
SDSS-DR4 with redshift information for the cluster members. We have derived
global properties for each cluster, such as their mean recessional velocity,
velocity dispersion, and virial radii. Cluster galaxies have been grouped in
two families according to their colours. The total sample consists of
10865 galaxies. As expected, the highest fraction of galaxies (62%) turned to
be early-type (red) ones, being located at smaller distances from the cluster
centre and showing lower velocity dispersions than late-type (blue) ones. The
brightest cluster galaxies are located in the innermost regions and show the
smallest velocity dispersions. Early-type galaxies also show constant velocity
dispersion profiles inside the virial radius and a mild decline in the
outermost regions. In contrast, late-type galaxies show always decreasing
velocity dispersions profiles. No correlation has been found between the
fraction of blue galaxies and cluster global properties, such as cluster
velocity dispersion and galaxy concentration. In contrast, we found correlation
between the X-ray luminosity and the fraction of blue galaxies. These results
indicate that early- and late-type galaxies may have had different evolution.
Thus, blue galaxies are located in more anisotropic and radial orbits than
early-type ones. Their star formation seems to be independent of the cluster
global properties in low mass clusters, but not for the most massive ones.
These observational results suggest that the global environment could be
important for driving the evolution of galaxies in the most massive cluster
( km s). However, the local environment could play a key
role in galaxy evolution for low mass clusters.Comment: 19 pages, 11 figures, accepted for publication in A&
Particle Physics Models of Inflation and the Cosmological Density Perturbation
This is a review of particle-theory models of inflation, and of their
predictions for the primordial density perturbation that is thought to be the
origin of structure in the Universe. It contains mini-reviews of the relevant
observational cosmology, of elementary field theory and of supersymmetry, that
may be of interest in their own right. The spectral index , specifying
the scale-dependence of the spectrum of the curvature perturbation, will be a
powerful discriminator between models, when it is measured by Planck with
accuracy . The usual formula for is derived, as well as
its less familiar extension to the case of a multi-component inflaton; in both
cases the key ingredient is the separate evolution of causally disconnected
regions of the Universe. Primordial gravitational waves will be an even more
powerful discriminator if they are observed, since most models of inflation
predict that they are completely negligible. We treat in detail the new wave of
models, which are firmly rooted in modern particle theory and have
supersymmetry as a crucial ingredient. The review is addressed to both
astrophysicists and particle physicists, and each section is fairly homogeneous
regarding the assumed background knowledge.Comment: 156 pages, after final proof corrections and addition
Iatrogenic aortic dissection after minimally invasive aortic valve replacement: a case report
Planck 2015 results. XIII. Cosmological parameters
We present results based on full-mission Planck observations of temperature and polarization anisotropies of the CMB. These data are consistent with the six-parameter inflationary LCDM cosmology. From the Planck temperature and lensing data, for this cosmology we find a Hubble constant, H0= (67.8 +/- 0.9) km/s/Mpc, a matter density parameter Omega_m = 0.308 +/- 0.012 and a scalar spectral index with n_s = 0.968 +/- 0.006. (We quote 68% errors on measured parameters and 95% limits on other parameters.) Combined with Planck temperature and lensing data, Planck LFI polarization measurements lead to a reionization optical depth of tau = 0.066 +/- 0.016. Combining Planck with other astrophysical data we find N_ eff = 3.15 +/- 0.23 for the effective number of relativistic degrees of freedom and the sum of neutrino masses is constrained to < 0.23 eV. Spatial curvature is found to be |Omega_K| < 0.005. For LCDM we find a limit on the tensor-to-scalar ratio of r <0.11 consistent with the B-mode constraints from an analysis of BICEP2, Keck Array, and Planck (BKP) data. Adding the BKP data leads to a tighter constraint of r < 0.09. We find no evidence for isocurvature perturbations or cosmic defects. The equation of state of dark energy is constrained to w = -1.006 +/- 0.045. Standard big bang nucleosynthesis predictions for the Planck LCDM cosmology are in excellent agreement with observations. We investigate annihilating dark matter and deviations from standard recombination, finding no evidence for new physics. The Planck results for base LCDM are in agreement with BAO data and with the JLA SNe sample. However the amplitude of the fluctuations is found to be higher than inferred from rich cluster counts and weak gravitational lensing. Apart from these tensions, the base LCDM cosmology provides an excellent description of the Planck CMB observations and many other astrophysical data sets