Earthquake Science Explained

This booklet features a collection of articles originally published for teachers by the San Francisco Chronicle. It presents some of the new understanding gained and scientific advances made in the century since the Great 1906 San Francisco Earthquake. Topics include lessons learned from the 1906 earthquake, the use of seismograms, recognizing active faults, and the use of trenches to investigate faults. There is also discussion of earthquake prediction, some hazards associated with earthquakes, making buildings and roads safer, and a career profile of an earthquake scientist. Concepts introduced in each feature are designed to address state and national science-education standards. Educational levels: Middle school, High school

God and the Gaps

Excerpt: Most often the story is told like this: There is some feature of the world that science is at a loss to explain. Christians rush to claim that this feature can only be explained by God. Science later produces probable non-theistic hypotheses, and the Christians must beat a hasty retreat. In the early nineteenth century, the feature was the complexity of life, the scientific explanation Darwinian evolution

The vacuum energy crisis

The smallness of the vacuum energy density and its near coincidence with the average matter density of the universe are naturally explained by anthropic selection. An alternative explanation, based on the cyclic model of Steinhardt and Turok, does not address the coincidence problem and is therefore less convincing. This article appeared in ``Science'' (4 May 2006) as a ``perspective'' for Steinhardt and Turok's paper in the same issue (astro-ph/0605173).Comment: 4 pages, no figures; invited "perspective" article in "Science" (4 May 2006

Elastic and non-linear stiffness of graphene: a simple approach

The recent experiment [Science \textbf{321}, 385 (2008)] on the Young's modulus and third-order elastic stiffness of graphene are well explained in a very simple approach, where the graphene is described by a simplified system and the force constant for the non-linear interaction is estimated from the Tersoff-Brenner potential.Comment: 4 pages, 4 figure

Explaining Creativity

Creativity has often been declared, especially by philosophers, as the last frontier of science. The assumption is that it will defy explanation forever. I will defend two claims in order to oppose this assumption and to demystify creativity: (1) the perspective that creativity cannot be explained wrongly identifies creativity with what I shall call metaphysical freedom; (2) the Darwinian approach to creativity, a prominent naturalistic account of creativity, fails to give an explanation of creativity, because it confuses conceptual issues with explanation. I will close with some remarks on the status and differences in some explanations available in contemporary cognitive science

Ab initio optical and energy loss spectra of transition metal monopnictides TaAs, TaP, NbAs, and NbP

Transition metal monopnictides represent a new class of topological semimetals with low-energy excitations, namely, Weyl fermions. We report optical properties across a wide spectral energy range for TaAs, TaP, NbAs and NbP, calculated within density functional theory. Spectra are found to be somewhat independent of the anion and the light polarization. Their features are explained in terms of the upper $s$, $p$, $d$, and $f$ electrons. Characteristic absorption features are related to the frequency dependence of the Fresnel reflectivity. While the lower part of the energy loss spectra is dominated by plasmonic features, the high-energy structures are explained by interband transitions.Comment: Added reference 21 to "S.-Y. Xu, et al, Science 349, 613 (2015)

Why do spatial abilities predict mathematical performance?

Spatial ability predicts performance in mathematics and eventual expertise in science, technology and engineering. Spatial skills have also been shown to rely on neuronal networks partially shared with mathematics. Understanding the nature of this association can inform educational practices and intervention for mathematical underperformance. Using data on two aspects of spatial ability and three domains of mathematical ability from 4174 pairs of 12-year-old twins, we examined the relative genetic and environmental contributions to variation in spatial ability and to its relationship with different aspects of mathematics. Environmental effects explained most of the variation in spatial ability (~70%) and in mathematical ability (~60%) at this age, and the effects were the same for boys and girls. Genetic factors explained about 60% of the observed relationship between spatial ability and mathematics, with a substantial portion of the relationship explained by common environmental influences (26% and 14% by shared and non-shared environments respectively). These findings call for further research aimed at identifying specific environmental mediators of the spatial–mathematics relationship