Virtual Processes and Quantum Tunnelling as Fictions

In this paper it is argued that virtual processes are dispensable fictions. The argument proceeds by a comparison with the phenomenon of quantum tunnelling. Building on an analysis of Lévy-Leblond and Balibar, it is argued that, although the phenomenon known as quantum tunnelling certainly occurs and is at the basis of many paradigmatic quantum effects, the implied conceptualization of it as a free particle burrowing through a potential barrier is flawed. An alpha particle, for example, does not exist as a free particle inside a uranium nucleus and then ??burrow through?? the massive potential barrier of the repulsive Coulomb potential: rather, it can be interpreted as existing in a bound state which gives it a corresponding (absolutely tiny, but) finite probability of appearing on the other side of the barrier. If the part of the state function representing the transmission through the barrier is conceived as representing a particle trajectory, the particle will have imaginary momentum and negative kinetic energy. A similar analysis then applies to virtual processes. For example, if (as in Hawking??s conception of black hole radiation) one imagines a pair of particles created at the Schwarzschild radius, one of which drops into the black hole, at its creation that particle will have imaginary momentum and negative kinetic energy; so will the pion that is imagined as mediating the nuclear exchange force on the standard model. In each case, it is argued, the phenomenon can be understood in terms of a finite probability of transmission predicted by quantum theory, without appealing to particle trajectories. The idea that a particle ??penetrates?? a barrier that it does not have the energy to surmount, or that a pair of particles is ??virtually?? produced one on either side of the Schwarzschild radius, in defiance of energy conservation, should be discarded as unphysical.     

Preschool writing and premathematics predict Grade 3 achievement for low-income,ethnically diverse children

The present study was designed to explore the association between preschool academic skills and Grade 3 achievement among a sample of ethnically diverse children from low-income families. Data were collected from a sample of 1,442 low-income, ethnically diverse children in preschool and associated with Grade 3 achievement in reading and mathematics 4 years later. Mixed-effects modeling indicated that preschool skills significantly predicted Grade 3 achievement measures while controlling for various child-level factors and random school effects. While several preschool factors were predictive of Grade 3 achievement, writing/copying and counting/premathematics skills were consistently strong predictors of Grade 3 achievement across all measures and domains suggesting these are important foundational skills for academic success in midelementary school among low-income, ethnically diverse children. Findings also replicate studies demonstrating that writing plays an important role in learning and achievement. Findings have implications for early education policy and practice intended to support academic development among low-income, ethnically diverse children.     

Critical action learning: a method or strategy for peer supervision of coaching practice

This paper deals with the on-going practice of a critical action learning set who come together to meet their needs for coaching supervision as a group of executive coaches working from, and within, the University sector in South Wales. The reasons for the successes of, and the challenges around, this practice of four years standing have been articulated using an academic backdrop. The use of multi-factorial supervision has been heralded as being able to give a more rounded form of supervision which, despite its challenges, has, in this example, stood the test of time. Further data are required to try to understand if this form of supervision provides better coaching to the executive field in South Wales and beyond, and what can be learnt from the practice of supervision in general.