Recent PublicationsView all

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We present a lattice QCD computation of η and η^{′} masses and mixing angles, for the first time controlling continuum and quark mass extrapolations. The results for M_{η}=551(8)_{stat}(6)_{syst} MeV and M_{η^{′}}=1006(54)_{stat}(38)_{syst}(+61)_{ex} MeV are in excellent agreement with experiment. Our data show that the mixing in the quark flavor basis can be described by a single mixing angle of ϕ=46(1)_{stat}(3)_{syst}° indicating that the η^{′} is mainly a flavor singlet state.
    Preview · Article · Oct 2013 · Physical Review Letters
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Using the framework of transformation optics, this paper presents a detailed analysis of a non-singular square cloak for acoustic, out-of-plane shear elastic and electromagnetic waves. Analysis of wave propagation through the cloak is presented and accompanied by numerical illustrations. The efficacy of the regularized cloak is demonstrated and an objective numerical measure of the quality of the cloaking effect is provided. It is demonstrated that the cloaking effect persists over a wide range of frequencies. As a demonstration of the effectiveness of the regularized cloak, a Young's double slit experiment is presented. The stability of the interference pattern is examined when a cloaked and uncloaked obstacle are successively placed in front of one of the apertures. This novel link with a well-known quantum mechanical experiment provides an additional method through which the quality of cloaks may be examined. In the second half of the paper, it is shown that an approximate cloak may be constructed using a discrete lattice structure. The efficiency of the approximate lattice cloak is analysed and a series of illustrative simulations presented. It is demonstrated that effective cloaking may be obtained by using a relatively simple lattice structure, particularly, in the low-frequency regime.
    Full-text · Article · Sep 2013 · Proceedings of The Royal Society A Mathematical Physical and Engineering Sciences
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Understanding models which represent the invasion of network-based systems by infectious agents can give important insights into many real-world situations, including the prevention and control of infectious diseases and computer viruses. Here we consider Markovian susceptible-infectious-susceptible (SIS) dynamics on finite strongly connected networks, applicable to several sexually transmitted diseases and computer viruses. In this context, a theoretical definition of endemic prevalence is easily obtained via the quasi-stationary distribution (QSD). By representing the model as a percolation process and utilising the property of duality, we also provide a theoretical definition of invasion probability. We then show that, for undirected networks, the probability of invasion from any given individual is equal to the (probabilistic) endemic prevalence, following successful invasion, at the individual (we also provide a relationship for the directed case). The total (fractional) endemic prevalence in the population is thus equal to the average invasion probability (across all individuals). Consequently, for such systems, the regions or individuals already supporting a high level of infection are likely to be the source of a successful invasion by another infectious agent. This could be used to inform targeted interventions when there is a threat from an emerging infectious disease.
    Full-text · Article · Jul 2013 · PLoS ONE
Information provided on this web page is aggregated encyclopedic and bibliographical information relating to the named institution. Information provided is not approved by the institution itself. The institution’s logo (and/or other graphical identification, such as a coat of arms) is used only to identify the institution in a nominal way. Under certain jurisdictions it may be property of the institution.
View all

Top publications last week by reads

Proceedings of the 12th UKSim, International Conference on Computer Modelling and Simulation, Cambridge, UK, 24-26 March 2010; 01/2010
14 Reads
Journal of Mathematical Analysis and Applications 02/2015; 422(1):684–711. DOI:10.1016/j.jmaa.2014.09.010
8 Reads