Universal one-way light speed from a universal light speed over closed paths

This paper gives two complete and elementary proofs that if the speed of light over closed paths has a universal value $c$, then it is possible to synchronize clocks in such a way that the one-way speed of light is c. The first proof is an elementary version of a recent proof. The second provides high precision experimental evidence that it is possible to synchronize clocks in such a way that the one-way speed of light has a universal value. We also discuss an old incomplete proof by Weyl which is important from an historical perspective.Comment: RevTex4, 6 pages, 2 figures, uses psfrag. New sections added, discussion expande

Impact of peer review audit on occupational health report quality

Background: In a previous report, we described the implementation of a formal process for peer review of occupational health (OH) reports and a method of assessment of the outcomes of this process. The initial audit identified that 27% of OH reports required modifications. Aims: To assess formally, following implementation of this process, if changes in practice had occurred, i.e. whether fewer deficiencies were being identified in reports. Methods: We repeated a prospective internal audit of all peer reviewed OH reports between September and November 2011. We used an abbreviated assessment form, based on questions 4–8 and 10–12 of the modified SAIL (Sheffield Assessment Instrument for Letters), with four possible outcomes: no action, no changes made to report following discussion with author, changes made without discussion with author and changes made following discussion with author. Results: One hundred seventy-three reports by 10 clinicians were audited. The audit identified a 13% reduction in OH reports requiring modifications (from 27 to 14%) compared with the previous cycle. Where modifications were required, 8% of these were related to minor typographical, spelling and grammar errors and 6% were for more complex reasons. Implementation of this process also produced a reduction in clinical complaints about OH reports from customers, from three in the preceding year to none 2 years later. Conclusions: Peer review improved the standard of OH reports and was associated with a reduction in customer complaints about reports

Greening information management: final report

As the recent JISC report on ‘the ‘greening’ of ICT in education [1] highlights, the increasing reliance on ICT to underpin the business functions of higher education institutions has a heavy environmental impact, due mainly to the consumption of electricity to run computers and to cool data centres. While work is already under way to investigate how more energy efficient ICT can be introduced, to date there has been much less focus on the potential environmental benefits to be accrued from reducing the demand ‘at source’ through better data and information management. JISC thus commissioned the University of Strathclyde to undertake a study to gather evidence that establishes the efficacy of using information management options as components of Green ICT strategies within UK Higher Education environments, and to highlight existing practices which have the potential for wider replication

On Multiple Zeta Values of Even Arguments

For k <= n, let E(2n,k) be the sum of all multiple zeta values with even arguments whose weight is 2n and whose depth is k. Of course E(2n,1) is the value of the Riemann zeta function at 2n, and it is well known that E(2n,2) = (3/4)E(2n,1). Recently Z. Shen and T. Cai gave formulas for E(2n,3) and E(2n,4). We give two formulas form E(2n,k), both valid for arbitrary k <=n, one of which generalizes the Shen-Cai results; by comparing the two we obtain a Bernoulli-number identity. We also give explicit generating functions for the numbers E(2n,k) and for the analogous numbers E*(2n,k) defined using multiple zeta-star values of even arguments.Comment: DESY number added; misprints fixed; reference added. Second revision (2016): New result on multiple zeta-star values adde

Quantum Hall Ferromagnetism in Graphene

Graphene is a two-dimensional carbon material with a honeycomb lattice and Dirac-like low-energy excitations. When Zeeman and spin-orbit interactions are neglected its Landau levels are four-fold degenerate, explaining the $4 e^2/h$ separation between quantized Hall conductivity values seen in recent experiments. In this paper we derive a criterion for the occurrence of interaction-driven quantum Hall effects near intermediate integer values of $e^2/h$ due to charge gaps in broken symmetry states.Comment: 4 pages, 1 figur

Generalised Calogero-Moser models and universal Lax pair operators

Calogero-Moser models can be generalised for all of the finite reflection groups. These include models based on non-crystallographic root systems, that is the root systems of the finite reflection groups, H_3, H_4, and the dihedral group I_2(m), besides the well-known ones based on crystallographic root systems, namely those associated with Lie algebras. Universal Lax pair operators for all of the generalised Calogero-Moser models and for any choices of the potentials are constructed as linear combinations of the reflection operators. The consistency conditions are reduced to functional equations for the coefficient functions of the reflection operators in the Lax pair. There are only four types of such functional equations corresponding to the two-dimensional sub-root systems, A_2, B_2, G_2, and I_2(m). The root type and the minimal type Lax pairs, derived in our previous papers, are given as the simplest representations. The spectral parameter dependence plays an important role in the Lax pair operators, which bear a strong resemblance to the Dunkl operators, a powerful tool for solving quantum Calogero-Moser models.Comment: 37 pages, LaTeX2e, no macro, no figur