- Full text PDF available (25)
A Chern-Simons action written with Christoffel Symbols has a natural gauge symmetry of diffeomorphisms. This Chern-Simons action will induce a Wess-Zumio-Witten model on the boundary of the manifold. If we restrict the diffeomorphisms to chiral diffeomorphism, the Wess-Zumio-Witten model is equivalent to a quantum Liouville action.
A software environment of unprecedented quality and functionality is emerging in which coupled computing resources are accessed via client-server and Web-based tools. This development is being driven by a combination of the computer industry, which is rapidly developing software for e-commerce and leisure use, and the loose collection of worldwide "… (More)
Single node performance is a key issue in the optimisation of codes for massively parallel processors, especially for applications like ocean and atmospheric modelling where high parallel efficiency is easily obtained from the natural data locality. In this paper we demonstrate how specific optimisations to suit a particular target processor architecture… (More)
The regular partitioning of grid based finite difference models for distribution onto parallel processors leads to a characteristic nearest neighbour boundary exchange communications pattern. In general the data structures to be exchanged are not contiguous in memory. OCCOMM is a low-level communications kernel benchmark which determines the performance of… (More)
Controlled environment (CE) and field experiments were done to investigate effects of fungicide on growth of L. maculans and L. biglobosa in relation to development of phoma leaf spots and phoma stem canker on oilseed rape. In CE experiments, for plants inoculated with L. maculans, fungicide treatment decreased lesion size and amount of L. maculans DNA in… (More)
Java has enjoyed a remarkable rise in popularity as the language of choice in a wide range of IT applications. High Performance and Data Intensive Computing has gone through a period of intense change as software environments have struggled to match the pace of developments in high performance hardware. There are now suggestions that Java may be able to… (More)
Accurately representing coastal and shelf seas in global ocean models represents one of the grand challenges of Earth system science. They are regions of immense societal importance through the goods and services they provide, hazards they pose and their role in global-scale processes and cycles, e.g. carbon fluxes and dense water formation. However , they… (More)
Coherent states possess a regularized path integral and gives a natural relation between classical variables and quantum operators. Recent work by Klauder and Whiting has included extended variables, that can be thought of as gauge fields, into this formalism. In this paper, I consider the next step, and look at the roll of first class constraints.