Suppressing Super-Horizon Curvature Perturbations?

We consider the possibility of suppressing superhorizon curvature perturbations after the end of the ordinary slow-roll inflationary stage. This is the opposite of the curvaton limit. We assume that large curvature perturbations are created by the inflaton and investigate if they can be diluted or suppressed by a second very homogeneous field which starts to dominate the energy density of the universe shortly after the end of inflation. We show explicit that the gravitational sourcing of inhomogeneities from the more inhomogeneous fluid to the more homogeneous fluid makes the suppression difficult if not impossible to achieve.Comment: 10 pages, 1 figure. Important revision. Conclusions more negativ

The Nelson and Winter Models RevisitedPrototypes for Computer-Based Reconstruction of Schumpeterian Competition

The report deals with the reconstruction and further development of the models of industrial dynamics developed by Nelson and Winter and summarised in their famous 1982-book. The basic idea underlying the Nelson and Winter models is that a verbal account of Schumpeterian competition can naturally be transformed into a description of a computational process in which firms not only make short-term production decisions and investment decisions but also performs a search for new technologies. The latter search is successful in a probabilistic manner, and its successes and failures determine an evolutionary process of the industry. Although the simulation models of Nelson and Winter have played a central role the ‘take-off’ of evolutionary economics, they have never been fully documented and their differences have never been explored. The resulting problems are obvious for students who start from Nelson’s and Winter’s most famous accounts, but even for researchers with a full collection of the underlying research papers, the situation is quite confusing. The report tries to make things easier by presenting overviews of the structure of Nelson and Winter models as well as fully implemented versions of their simulation models – especially NELWIN78 based on ch. 13 of the 1982-book and NELWIN77 based on ch. 12. The report furthermore presents a computer-based environment (implemented in MAPLE V Rev2) for revision of the models and for analysis of the overwhelming number of data resulting from simulation runs.Evolutionary economic modelling, simulation of industrial dynamics, Schumpeterian competit

The Matrix Reloaded - on the Dark Energy Seesaw

We propose a novel mechanism for dark energy, based on an extended seesaw for scalar fields, which does not require any new physics at energies below the TeV scale. A very light quintessence mass is usually considered to be technically unnatural, unless it is protected by some symmetry broken at the new very light scale. We propose that one can use an extended seesaw mechanism to construct technically natural models for very light fields, protected by SUSY softly broken above a TeV

Recent developments Mudzuru & Another v The Minister of Justice, Legal and Parliamentary Affairs & 2 Others: A review

This article reviews the recent judgment of the Constitutional Court of Zimbabwe in Mudzuru & Another v The Minister of Justice, Legal and Parliamentary Affairs & 2 Others, which has been hailed with acclaim worldwide. The review highlights three areas where the judgment makes a significant jurisprudential contribution: first, with respect to the issue of standing to bring a constitutional challenge under the Zimbabwean Constitution; second, with respect to the use of international treaty law and foreign case law; and third, in its purposive approach to the interpretation of the relevant constitutional provisions relating to child marriage. The regional impact of the decision is also considered in relation to recent litigation in Tanzania.DHE

Extracellular Vesicles:An Important Biomarker in Recurrent Pregnancy Loss?

Recurrent pregnancy loss (RPL) has an estimated incidence of 1–3% of all couples. The etiology is considered to be multifactorial. Extracellular vesicles (EVs) take part in numerous different physiological processes and their contents show the originating cell and pathophysiological states in different diseases. In pregnancy disorders, changes can be seen in the composition, bioactivity and concentration of placental and non-placental EVs. RPL patients have an increased risk of pregnancy complications. The aim of this prospective study was to examine whether measuring different specific EV markers in plasma before and during pregnancy could be used as predictors of pregnancy loss (PL) in women with RPL. Thirty-one RPL patients were included in this study; 25 had a live birth (LB group) and six had a new PL (PL group). Five blood samples were obtained, one before achieved pregnancy and the others in gestational week 6, 8, 10 and 16. Moreover, some of the patients received intravenous immunoglobulin (IVIG) infusions as part of treatment, and it was also examined whether this treatment influenced the EV levels. Seventeen EV markers specific for the immune system, coagulation, placenta and hypoxia were analyzed in the samples with EV Array, a method able to capture small EVs by using an antibody panel targeting membrane proteins. Comparing the LB and PL groups, one EV marker, CD9, showed a significant increase from before pregnancy to gestational week 6 in the PL group. The changes in the other 16 markers were nonsignificant. One case of late-onset PL showed steeply increasing levels, with sudden decrease after gestational week 10 in nine of 17 markers. Moreover, there was an overall increase of all 17 markers after IVIG treatment in the LB group, which was significant in 15 of the markers. Whether increases in EVs positive for CD9 characterize RPL patients who subsequently miscarry should be investigated in future larger studies

A new diagrammatic representation for correlation functions in the in-in formalism

In this paper we provide an alternative method to compute correlation functions in the in-in formalism, with a modified set of Feynman rules to compute loop corrections. The diagrammatic expansion is based on an iterative solution of the equation of motion for the quantum operators with only retarded propagators, which makes each diagram intrinsically local (whereas in the standard case locality is the result of several cancellations) and endowed with a straightforward physical interpretation. While the final result is strictly equivalent, as a bonus the formulation presented here also contains less graphs than other diagrammatic approaches to in-in correlation functions. Our method is particularly suitable for applications to cosmology.Comment: 14 pages, matches the published version. includes a modified version of axodraw.sty that works with the Revtex4 clas

Tracking Curvaton(s)?

The ratio of the curvaton energy density to that of the dominant component of the background sources may be constant during a significant period in the evolution of the Universe. The possibility of having tracking curvatons, whose decay occurs prior to the nucleosynthesis epoch, is studied. It is argued that the tracking curvaton dynamics is disfavoured since the value of the curvature perturbations prior to curvaton decay is smaller than the value required by observations. It is also argued, in a related context, that the minimal inflationary curvature scale compatible with the curvaton paradigm may be lowered in the case of low-scale quintessential inflation.Comment: 20 pages, 4figure