Zero to Infinity A Review of Charles Seife’s ZERO: The Biography of a Dangerous Idea

“Nil”, “Nunca”, “Nada”, “Nil”, “Nothing”, “Zero”. Sounds of a multilingual class of mathematics, perhaps. No, it is the sounds around the family table card game as we all declare the number of tricks that we would like to take in a card game called Wizard. The speaker is telling the scorekeeper that they would not like to take any tricks. They would like to take “zero” tricks as if they could gather the zero cards. We all know that we do not want any tricks and we do our best not to take any if we declare that we want zero tricks

Gender digital divide and challenges in undergraduate computer science programs

Previous research revealed a reduced number of female students registered in computer science studies feeling isolated, having reduced confidence, and underperforming. This article explores differences between female and male students in undergraduate computer science programs in a mid-size university in Ontario. Based on Kelly's (2008) three levels of digital divide (resources, instruction, and culture specific knowledge), we explored gender specific challenges for each level. The research shows that, while the first level of digital divide is difficult to detect and the second layer is easily detectable, the third layer of digital divide is particularly pervasive and has a disconcerting outcome.  Key words: digital divide; computer science education; higher education; gender equity.Des recherches antérieures ont révélé un nombre réduit d'étudiantes inscrites dans les études d'informatique. En outre, les élèves restants se sentent isolées, ont réduit la confiance, et sous-performer. Cet article explore les différences entre les étudiants et étudiantes de premier cycle dans les programmes d'informatique dans une université de moyenne dimension en Ontario. Sur la base de Kelly (2008), trois niveaux de la fracture numérique (ressources, l'enseignement et la culture des connaissances spécifiques), nous avons exploré les défis spécifiques au genre pour chaque niveau. La recherche montre que, tandis que le premier niveau de la fracture numérique est difficile à détecter et la deuxième couche est facilement détectable, la troisième couche de la fracture numérique est particulièrement répandue et a un dénouement déconcertant.Mots clés: fracture numérique, enseignement de l'informatique, l'enseignement supérieur, l'équité entre les sexe

The Collaborative Teacher Inquiry Project: A Purposeful Professional Development Initiative

The transition from Grade 8 to Grade 9 is particularly difficult for students who were not very successful in mathematics in Grade 8. Research into ways to improve this transition as well as improve the teaching practices at the Applied level will be helpful for teachers, administrators, and policy makers. The Collaborative Teacher Inquiry Project was a professional development initiative that brought together educators from nine schools across four neighbouring school districts in Ontario seeking to improve their Grade 9 Applied Mathematics program. As part of the Collaborative Teacher Inquiry Project, participants attended topic-specific workshops based on schools’ goals for professional growth and had opportunities to collaborate with other participants to create and share teaching materials for the Grade 9 Applied Mathematics course. Qualitative data from teacher interviews and written reflections indicate that the teachers felt that a mixture of collaboration and professional development made this project successful. Teachers also reported that the Collaborative Teacher Inquiry Project motivated further collaboration at the school and district level

Particle Production in a Gravitational Wave Background

In this article, the authors study the possibility that massless particles, such as photons, are produced by a gravitational wave. That such a process should occur is implied by tree-level Feynman diagrams such as two gravitons turning into two photons, i.e., g + g → γ + γ. Here we calculate the rate at which a gravitational wave creates a massless scalar field. This is done by placing the scalar field in the background of a plane gravitational wave and calculating the 4-current of the scalar field. Even in the vacuum limit of the scalar field it has a nonzero vacuum expectation value (similar to what occurs in the Higgs mechanism) and a nonzero current. We associate this with the production of scalar field quanta by the gravitational field. This effect has potential consequences for the attenuation of gravitational waves since the massless field is being produced at the expense of the gravitational field. This is related to the time-dependent Schwinger effect, but with the electric field replaced by the gravitational wave background and the electron/positron field quanta replaced by massless scalar “photons.” Since the produced scalar quanta are massless there is no exponential suppression, as occurs in the Schwinger effect due to the electron mass

Particle Production in a Gravitational Wave Background

In this article, the authors study the possibility that massless particles, such as photons, are produced by a gravitational wave. That such a process should occur is implied by tree-level Feynman diagrams such as two gravitons turning into two photons, i.e., g + g → γ + γ. Here we calculate the rate at which a gravitational wave creates a massless scalar field. This is done by placing the scalar field in the background of a plane gravitational wave and calculating the 4-current of the scalar field. Even in the vacuum limit of the scalar field it has a nonzero vacuum expectation value (similar to what occurs in the Higgs mechanism) and a nonzero current. We associate this with the production of scalar field quanta by the gravitational field. This effect has potential consequences for the attenuation of gravitational waves since the massless field is being produced at the expense of the gravitational field. This is related to the time-dependent Schwinger effect, but with the electric field replaced by the gravitational wave background and the electron/positron field quanta replaced by massless scalar “photons.” Since the produced scalar quanta are massless there is no exponential suppression, as occurs in the Schwinger effect due to the electron mass

Research on Reform in Mathematics Education, 1993-2000

Proponents and opponents of reform of mathematics education all cite the research base in support of their positions. This article reports the results of a review of studies that contained empirical evidence of the effects of reform or the difficulty of implementing reform that were published between 1993 and 2000. The studies reviewed indicate that implementation of math reform contributes to student achievement, but evidence abounds of superficial implementation and barriers to enactment. There are well-documented strategies for reducing these barriers, the most promising strategies being inservice that simultaneously focuses on teachers' practice and their cognition about mathematics teaching.Promoteurs et adversaires d'une réforme en enseignement des mathématiques puisent tous dans la recherche pour appuyer leurs points de vue. Cet article présente le résultat d'une analyse d'études empiriques publiées entre 1993 et 2000 et qui évoquent les effets d'une réforme ou la difficulté d'en mettre une en application. Selon les études analysées, la mise en œuvre d'une réforme en enseignement des mathématiques contribue aux réalisations des élèves. Toutefois, énormément d'articles évoquent une mise en œuvre superficielle et des obstacles à la réforme. Parmi les stratégies bien documentées pour minimiser ces obstacles, celles qui promettent le plus impliquent une formation pour enseignants en cours d'emploi qui touche à la fois les méthodes des enseignants et leurs connaissances sur l'enseignement des mathématiques

‘Stay safe online, tell someone’ evaluation report

[Extract] Introduction Children and young people are spending more time online than ever before. In addition to other forms of abuse and harm, online abuse—including sexual abuse, grooming, sextortion, child sexual abuse (CSA) material related offenses and cyberbullying—is a concern that must be addressed. The Y developed and evaluated an adapted version of the ‘Stay Safe, Tell Someone’ program. The ‘Stay Safe Online, Tell Someone’ program was developed through adapting the existing program using data analysed from focus groups with children and young people and utilises an online/digital delivery method. The aim of the program is to increase program users’ resilience, confidence and perception of online safety, and to ensure users have the information they need to have their voices heard and to go to someone if they have concerns or worries

Scalar Field Vacuum Expectation Value Induced by Gravitational Wave Background

We show that a massless scalar field in a gravitational wave background can develop a non-zero vacuum expectation value. We draw comparisons to the generation of a non-zero vacuum expectation value for a scalar field in the Higgs mechanism and with the dynamical Casimir vacuum. We propose that this vacuum expectation value, generated by a gravitational wave, can be connected with particle production from gravitational waves and may have consequences for the early Universe where scalar fields are thought to play an important role

Who Produces for Whom in the World Economy?

International audienceFor two decades, the share of trade in inputs, also called vertical trade, has been dramatically increasing. In reallocating trade flows to their original input-producing industries and countries, this paper suggests a new measure of international trade: "value-added trade" and makes it possible to answer the question "who produces for whom?". In 2004, 27% of international trade was vertical trade. The industrial and geographic patterns of value-added trade are very different from those of standard trade. Value-added trade is relatively less important in regional trade but the difference is not more important for Asia than for AmericaLa part du commerce en produits intermédiaires dans le commerce international, appelé aussi "commerce vertical", n'a cessé d'augmenter depuis vingt ans. Cet article propose une nouvelle mesure du commerce international "le commerce en valeur ajoutée" qui réalloue les flux commerciaux aux pays et aux secteurs produisant les intrants. Les répartitions géographique et sectorielle du commerce en valeur ajoutée sont très différentes de celles du commerce " standard ". La différence entre le commerce en valeur ajoutée et le commerce standard est plus importante dans le cas du commerce régional mais ce n'est pas plus le cas en Asie qu'en Amérique