Myrsilus of Methymna and the Dreadful Smell of the Lemnian Women

published or submitted for publicatio

Geometric RG Flow

We define geometric RG flow equations that specify the scale dependence of the renormalized effective action Gamma[g] and the geometric entanglement entropy S[x] of a QFT, considered as functionals of the background metric g and the shape x of the entanglement surface. We show that for QFTs with AdS duals, the respective flow equations are described by Ricci flow and mean curvature flow. For holographic theories, the diffusion rate of the RG flow is much larger, by a factor R_{AdS}^2/\ell_s^2, than the RG resolution length scale. To derive our results. we employ the Hamilton-Jacobi equations that dictate the dependence of the total bulk action and the minimal surface area on the geometric QFT boundary data.Comment: 20 pages, 3 figure

Creating virtual communities of practice for learning technology in higher education: Issues, challenges and experiences

The need for a Web portal to support the rapidly growing field of learning technology has been well established through a number of national surveys and scoping studies over recent years. The overarching vision has been the provision of a virtual environment to assist in informing and developing professional practice in the use of learning technologies. This paper outlines the issues and challenges in creating such a portal through the experiences of developing the RESULTs Network. In the paper, design and participation issues are considered within the wider context of online and networked approaches to supporting practice and professional development. User participation methodologies and technical developments for RESULTs are described in relation to a review of existing representations of practice and a comprehensive survey amongst the learning technology users’ community. An outline of key achievements and experiences is presented, followed by some conclusions regarding the cultural and political issues in creating a viable and sustainable facility and suggestions for possible future direction in national provision

The Impact of Ambient Temperature on Low Carbon Energy Supply - Modelling and optimization studies on the supply of hydrogen energy from northern Norway

To avoid the worst impacts of climate change a rapid green energy transition is required where traditional fossil fuels are replaced by low-carbon alternatives. One attractive route to emissions reduction is blue hydrogen, which has lower CO2 emissions that traditional hydrogen production. For hydrocarbon exporters, increased blue hydrocarbon production can be achieved in two main ways: continued gas export with end-user-based hydrogen production or in-country hydrogen production and export. The cold climate in Norway provides a particular advantage to the performance of some industrial processes. A good example of this being the LNG plant at Melkøya, which is the most efficient of its type. Several other processes associated with blue hydrogen production could also benefit from low ambient temperature, increasing the attractiveness of in-country hydrogen production and potentially better supporting a future green hydrogen economy. The work summarised in this thesis includes a set of process optimization studies that look at the impact of ambient temperature on performance for several key links in the blue hydrogen supply chain. Along with this, a supply chain model is developed for a scenario where hydrogen is supplied from northern Norway to the UK. The focus of the work is process modelling and optimization, and several new sets of performance data are developed for important industrial processes. The main conclusion of this study is that the advantage offered by low ambient temperature in northern Norway is sufficient to make the export of blue hydrogen more efficient that a conventional LNG export based scenario over a range of realistic operating cases. The implication of this is that the basis for projects based on a conventional approach should be considered in more detail to ensure that they are based on a sound footing