Higgsino dark matter in partly supersymmetric models

Models where supersymmetry (SUSY) is manifest only in a sector of the low-energy spectrum have been recently proposed as an alternative to the MSSM. In these models the electroweak scale is explained by a fine-tuning between different Higgs mass contributions (split-SUSY models), or by the localization of the Higgs sector in a point of an extra dimension where all the mass parameters are suppressed by the metric (partly-SUSY models). Therefore, the presence of a good dark matter candidate becomes the main motivation for (partial) low-energy SUSY. We study this issue in minimal frameworks where the higgsinos are the only light supersymmetric particles. Whereas in split-SUSY models the higgsino should have a mass around 1 TeV, we show that in partly-SUSY models the lightest higgsino could also be found below MW.Comment: 12 pages, 3 figures, version to appear in Phys. Rev.

On the criticality of inferred models

Advanced inference techniques allow one to reconstruct the pattern of interaction from high dimensional data sets. We focus here on the statistical properties of inferred models and argue that inference procedures are likely to yield models which are close to a phase transition. On one side, we show that the reparameterization invariant metrics in the space of probability distributions of these models (the Fisher Information) is directly related to the model's susceptibility. As a result, distinguishable models tend to accumulate close to critical points, where the susceptibility diverges in infinite systems. On the other, this region is the one where the estimate of inferred parameters is most stable. In order to illustrate these points, we discuss inference of interacting point processes with application to financial data and show that sensible choices of observation time-scales naturally yield models which are close to criticality.Comment: 6 pages, 2 figures, version to appear in JSTA

Piloting a holistic information culture program: The experience of CETYS Universidad system of libraries

This article presents the staff, structure, methods and preliminary results from the pilot of a holistic information literacy program developed in the System of Libraries of CETYS Universidad in Mexico. ‘Information Culture Development’ (ICD) is driven by action research (AR) and the concept of information culture (IC), comprised of information literacy (IL), digital literacy (DL), and research competences. ICD aims at developing these competences and supporting reflection and improvement upon university practices related to curriculum, teaching, and research. ICD’s initiatives and products were divided into four axes: a) curriculum and learning support, b) information and digital literacies development, c) research and scientific communication support, and d) evaluation and communication of results. ICD’s pilot involved workshops and activities framed within an AR perspective and a mixed methods approach. Preliminary results determine the success of activities with academics and students regarding their strengths and weaknesses in IC-related competencies

Evaluation of the material’s damage in gas turbine rotors by instrumented spherical indentation

Experimental indentations are carried out on items of two different materials, taken in severallocation of various components from high pressure gas turbine rotor which have seen an extensive service. Thecomponents object of investigation consisted in 1st and 2nd high pressure turbine wheels made in nickel-basesuperalloy (Inconel 718), the spacer ring (Inconel 718) and the compressor shaft made in CrMoV low alloy steel(ASTM A471 type10).Aim of the work is to set up the capability of the instrumented spherical indentation testing system to evaluatevariations in the material properties due to damage, resulting from temperature field and stresses acting oncomponents during service. To perform this task load-indentation depth curves will be acquired in variouszones of the above mentioned components. The analysis of the results has allowed to identify an energyparameter which shows a linear evolution with the mean temperature acting on the components

Financial correlations at ultra-high frequency: theoretical models and empirical estimation

A detailed analysis of correlation between stock returns at high frequency is compared with simple models of random walks. We focus in particular on the dependence of correlations on time scales - the so-called Epps effect. This provides a characterization of stochastic models of stock price returns which is appropriate at very high frequency.Comment: 22 pages, 8 figures, 1 table, version to appear in EPJ

Individual Rights, Economic Transactions, and Recognition: A Legal Approach to Social Economics

Modernity brought the idea of individual property rights as a com- plex phenomenon. However, economics adopted a simplistic view of property as a fundamental institution, understating the complex interaction of different rights and obligations that frame the legal environment of economic processes with an insufficiently elaborated tool. Here, a more elaborate view of legal elements will be propose

Beyond inverse Ising model: structure of the analytical solution for a class of inverse problems

I consider the problem of deriving couplings of a statistical model from measured correlations, a task which generalizes the well-known inverse Ising problem. After reminding that such problem can be mapped on the one of expressing the entropy of a system as a function of its corresponding observables, I show the conditions under which this can be done without resorting to iterative algorithms. I find that inverse problems are local (the inverse Fisher information is sparse) whenever the corresponding models have a factorized form, and the entropy can be split in a sum of small cluster contributions. I illustrate these ideas through two examples (the Ising model on a tree and the one-dimensional periodic chain with arbitrary order interaction) and support the results with numerical simulations. The extension of these methods to more general scenarios is finally discussed.Comment: 15 pages, 6 figure

Lay People Representations on the Common Good and Its Financial Provision

The financial contribution to the common good is a relevant issue to contemporary societies, especially in the wake of the Global Financial Crisis. In the economic literature, taxes and monetary donations have been regarded as two complementary ways of financially providing for the common good. In the psychological literature, instead, they have not been studied in conjunction. In-depth interviews have been conducted using interpretative phenomenological analysis (IPA) approach and a photo-elicitation technique to investigate the representations people share on the financial provision for the common good. Results suggest that both taxes and donations are seen as indirect, rather than direct, ways of providing for the common good. From a formal and cognitive level, paying taxes and making donations can be seen as two sides of the same coin, but they present differences at the affective level. When paying taxes, people are concerned mostly about the effects and expect a material exchange in return; when making a monetary donation, people are concerned mostly about the motivations and expect an emotional exchange in return