On the accretion of phantom energy onto wormholes

By using a properly generalized accretion formalism it is argued that the accretion of phantom energy onto a wormhole does not make the size of the wormhole throat to comovingly scale with the scale factor of the universe, but instead induces an increase of that size so big that the wormhole can engulf the universe itself before it reaches the big rip singularity, at least relative to an asymptotic observer.Comment: 4 pages, LaTex, to appear in Phys. Lett.

Dynamic Renormalization Group Approach to Self-Organized Critical Phenomena

Two different models exhibiting self-organized criticality are analyzed by means of the dynamic renormalization group. Although the two models differ by their behavior under a parity transformation of the order parameter, it is shown that they both belong to the same universality class, in agreement with computer simulations. The asymptotic values of the critical exponents are estimated up to one loop order from a systematic expansion of a nonlinear equation in the number of coupling constants.Comment: 8 pages, RevTeX 3.0, 1 PostScript figure available upon reques

Using fMRI in experimental philosophy: Exploring the prospects

This chapter analyses the prospects of using neuroimaging methods, in particular functional magnetic resonance imaging (fMRI), for philosophical purposes. To do so, it will use two case studies from the field of emotion research: Greene et al. (2001) used fMRI to uncover the mental processes underlying moral intuitions, while Lindquist et al. (2012) used fMRI to inform the debate around the nature of a specific mental process, namely, emotion. These studies illustrate two main approaches in cognitive neuroscience: Reverse inference and ontology testing, respectively. With regards to Greene et al.’s study, the use of Neurosynth (Yarkoni 2011) will show that the available formulations of reverse inference, although viable a priori, seem to be of limited use in practice. On the other hand, the discussion of Lindquist et al.’s study will present the so far neglected potential of ontology-testing approaches to inform philosophical questions

Artificial Neural Nets with Interaction of Afferents

The aim is to obtain computationally more powerful, neuro physiologically founded, artificial neurons and neural nets. Artificial Neural Nets (ANN) of the Perceptron type evolved from the original proposal by McCulloch an Pitts classical paper [1]. Essentially, they keep the computing structure of a linear machine followed by a non linear operation. The McCulloch-Pitts formal neuron (which was never considered by the author’s to be models of real neurons) consists of the simplest case of a linear computation of the inputs followed by a threshold. Networks of one layer cannot compute anylogical function of the inputs, but only those which are linearly separable. Thus, the simple exclusive OR (contrast detector) function of two inputs requires two layers of formal neuron

The irony of choice in recruitment: when similarity turns recruiters to other candidates

Across two experimental studies, we examine the influence of similarity perceptions on recruiters’ job fit perceptions of job applicants. In addition, a robustness study extends the effect of similarity by introducing work-related sources of similarity and tests the relationship between workrelated similarities on similarity perceptions. Moreover, we explore the emotional and cognitive mechanisms behind the effects of similarity perceptions on job fit. We also propose and test a boundary condition, such that, when job desirability is low, the effect of demographic similarity on perceived similarity is reversed. The sample for the three studies consist of specialized master’s students with work experience in human resources management who acted as recruiters in a resume screening situation. The results show that the effects of similarity are not always positive for job fit perceptions. The studies provide evidence that when recruiters perceive applicants as similar to themselves, biased evaluations occur. Finally, we provide results that show the effects of mediation and moderation analysis whereby liking mediates the relationship between similarity perceptions and job fit perceptions through emotional, cognitive and motivational sequential mediators. Additionally, job desirability moderates the relationship between demographic similarity and similarity perceptions so that when job desirability is low, the effect of demographic similarity on perceived similarity is reversed