Mathematics, computers in mathematics, and gender: public perceptions in context

In Australia, national tests of mathematics achievement continue showing small but consistent gender differences in favor of boys. Societal views and pressures are among the factors invoked to explain such subtle but persistent differences. In this paper we focus directly on the beliefs of the general public about students’ learning of mathematics and the role played by computers, and then we compare the findings with data previously gathered from students. Although many considered it inappropriate to differentiate between boys and girls, gender based stereotyping was still evident

Infrared analysis of propagators and vertices of Yang--Mills theory in Landau and Coulomb gauge

The infrared behaviour of gluon and ghost propagators, ghost-gluon vertex and three-gluon vertex is investigated for both the covariant Landau and the non-covariant Coulomb gauge. Assuming infrared ghost dominance, we find a unique infrared exponent in the d=4 Landau gauge, while in the d=3+1 Coulomb gauge we find two different infrared exponents. We also show that a finite dressing of the ghost-gluon vertex has no influence on the infrared exponents. Finally, we determine the infrared behaviour of the three-gluon vertex analytically and calculate it numerically at the symmetric point in the Coulomb gauge.Comment: 25 pages, 6 figures, accepted by Phys. Rev. D, references added, typos correcte

Facing the Sublime: Physiological Correlates of the Relationship Between Fear and the Sublime

The sublime is an enduring concept in Western aesthetic discourse and is often portrayed such as in Edmund Burke’s A Philosophical Enquiry into the Origin of Our Ideas of the Sublime and Beautiful of 1759 as a delightful horror, a kind of enjoyment based on negative emotions. In the current article, the relationship between sublimity and fear was explored using behavioral and physiological measures. In 2 studies (total N ≈ 120), photographs of nature were selected (Study 1: 192 photographs and Study 2: 72 photographs), rated on sublimity, beauty, fear, happiness, and arousal, before being assessed against facial muscle movement (fEMG) and skin conductance (SCR). In line with philosophical theories, ratings of sublimity showed positive associations with subjective fear ratings in both studies. Looking at fEMG data (Study 2), sublimity was in fact associated with a decrease of corrugator supercilli (frowning) reactions, indicating reduced emotional negativity. Furthermore, sublimity did not change activation levels of the zygomaticus major (smiling/positive emotional valence), nor did it influence movements of the medial frontalis (inner brow raise/fear). Increased ratings of fear increased corrugator supercilii and medial frontalis activations, and decreased zygomaticus major activation, replicating past findings. SCR activation was not predicted by any variable. The discrepancy between behavioral and physiological results likely results from a combination of false appraisal and distancing mechanisms, and thus encourages the reconsideration of generalizations made over the sublime in its relation to fear

Linear and nonlinear optical characteristics of the Falicov-Kimball model

We calculate the linear and nonlinear optical properties of the Falicov-Kimball model for a mixed-valent system within the self-consistent mean-field approximation. Second-harmonic generation can only occur if the mixed-valent state has a built-in coherence between the itinerant d-electrons and the localized f-holes. By contrast, second-harmonic generation cannot occur for solutions of the model with f-site occupation as a good quantum number. As an experimental test of coherence in mixed-valent compounds we propose a measurement of the dynamic second-order susceptibility.Comment: 4 pages, 2 PostScript figures, to appear in Physical Review Letter

Functional approaches to infrared Yang-Mills theory in the Coulomb gauge

We present the current status of ongoing efforts to use functional methods, Dyson-Schwinger equations and functional renormalization group equations, for the description of the infrared regime of nonabelian (pure) gauge theories in the Coulomb gauge. In particular, we present a new determination of the color-Coulomb potential with the help of the functional renormalization group that results in an almost linearly rising potential between static color charges at large spatial distances.Comment: 11 pages, 3 figures. Slightly improved version of J. Phys.: Conf. Ser. 287 (2011) 01202

Quantifying the If, the When, and the What of the Sublime: A Survey and Latent Class Analysis of Incidence, Emotions, and Distinct Varieties of Personal Sublime Experiences

Sublime encounters provide a compelling example of the peaks of our shared emotional and cognitive experiences. For centuries, these have been a target for philosophy and, more recently, for psychology, with its renewed focus on profound or aesthetic events. The sublime has been theoretically connected to multiple contexts, from interactions with overpowering nature, to beauty, music, even interpersonal engagements, and to multiple emotions—danger, awe, pleasure, fear—often with diametrically opposing arguments for what constitutes these events. However, despite this prolonged discussion, there is still a scarcity of actual systematic research. It is not known whether sublime encounters are common, nor how they are described by individuals, or if reports match theoretical arguments: Are there one or more, or no, distinct sublime types? We address these questions by matching historical discussions to 402 participants’ (Western adults) reports of whether they have ever experienced the sublime and, if so, how these are described in terms of cognitive/emotional and contextual factors. Roughly half reported having had at least one sublime experience, with accounts involving a range of contexts that essentially cover the full spectrum of past theoretical arguments. At the same time, when we considered the cognitive/affective descriptions using network science and latent class analysis of reported feelings, 90.8% fit one model, with involved communities (or interrelated clusters) of positive emotions, discrepancy, self-awareness, transformation/insight, and, notably, not including negative emotions/fear. We conclude with a discussion of how this approach and findings might be used as a basis for considering sublime theory and shaping future research