African University of Science and Technology: Recent submissions

Now showing items 661-680 of 4824

  • Minimal Massive 3D Gravity Unitarity Redux 

    Arvanitakis, Alex S; Townsend, Paul Kingsley (IOPClassical and Quantum Gravity, 2015-02-26)
    A geometrical analysis of the bulk and anti-de Sitter boundary unitarity conditions of 3D “Minimal Massive Gravity” (MMG) (which evades the “bulk/boundary clash” of Topologically Massive Gravity) is used to extend and ...

  • Limits on a Gravitational Field Dependence of the Proton{Electron Mass Ratio from H2 in White Dwarf Stars 

    Bagdonaite, J; Salumbides, EJ; Preval, SP; Barstow, MA; Barrow, John David; Murphy, MT; Ubachs, W (American Physical SocietyPhysical Review Letters, 2014-09-18)
    Spectra of molecular hydrogen (H2) are employed to search for a possible proton-to-electron mass ratio (μ) dependence on gravity. The Lyman transitions of H2, observed with the Hubble Space Telescope towards white dwarf ...

  • Explaining the CMS eejj Excess With R−parity Violating Supersymmetry and Implications for Neutrinoless Double Beta Decay 

    Allanach, Benjamin Christopher; Biswas, Sanjoy; Mondal, Subhadeep; Mitra, Manimala (American Physical SocietyPhysical Review D, 2015-01-28)
    The recent CMS searches for the right handed gauge boson WR reports an interesting deviation from the Standard Model. The search has been conducted in the eejj channel and has shown an excess around meejj ~ 2 TeV. In this ...

  • Resonant slepton production yields CMS eejj and epTjj excesses 

    Allanach, Benjamin Christopher; Biswas, Sanjoy; Mondal, Subhadeep; Mitra, Manimala (APS, 2015-01-13)
    Recent CMS searches for dileptoquark production report local excesses of 2.4σ in an eejj channel and 2.6σ in an epTjj channel. Here, we simultaneously explain both excesses with resonant slepton production in R-parity ...

  • Maximum Tension: with and without a cosmological constant 

    Barrow, John David; Gibbons, Gary William (OUPMonthly Notices of the Royal Astronomical Society, 2014-12-04)
    We discuss various examples and ramifications of the conjecture that there exists a maximum force (or tension) in general relativistic systems. We contrast this situation with that in Newtonian gravity, where no maximum ...

  • Quantum theory from the perspective of general probabilistic theories 

    Al-Safi, Sabri Walid (University of CambridgeDepartment of Applied Mathematics and Theoretical Physics, 2015-03-03)
    This thesis explores various perspectives on quantum phenomena, and how our understanding of these phenomena is informed by the study of general probabilistic theories. Particular attention is given to quantum nonlocality, ...

  • Multiple solutions in supersymmetry and the Higgs 

    Allanach, Benjamin Christopher (The Royal Society PublishingPhilosophical Transactions of the Royal Society A, 2014-11-24)
    Weak-scale supersymmetry is a well-motivated, if speculative, theory beyond the Standard Model of particle physics. It solves the thorny issue of the Higgs mass, namely: how can it be stable to quantum corrections, when ...

  • Jordan-Wigner formalism for arbitrary 2-input 2-output matchgates and their classical simulation 

    Jozsa, Richard; Miyake, Akimasa; Strelchuk, Sergii (Rinton PressQuantum Information and Computation, 2015-05-01)
    In Valiant's matchgate theory, 2-input 2-output matchgates are 4 4 matrices that satisfy ten so-called matchgate identities. We prove that the set of all such matchgates (including non-unitary and non-invertible ones) ...

  • The convective desalination of sea ice 

    Rees Jones, David (University of CambridgeDepartment of Applied Mathematics and Theoretical Physics, 2014-07-01)
    This thesis aims to improve our understanding of the fundamental processes affecting the growth of sea ice in the polar oceans in order to improve climate models. Newly formed sea ice contains a significant amount of salt ...

  • Asymptotic approximations for the sound generated by aerofoils in unsteady subsonic flows 

    Ayton, Lorna Jane (University of CambridgeDepartment of Applied Mathematics and Theoretical PhysicsChurchill College, 2014-10-07)
    This thesis considers the sound generated by unsteady perturbations interacting with solid aerofoils in background steady flows, in an attempt to further develop analytic models for the noise generated by blades within ...

  • Secondary instability and tertiary states in rotating plane Couette flow 

    Daly, CA; Schneider, Tobias M; Schlatter, Philipp; Peake, Nigel (Cambridge University PressJournal of Fluid Mechanics, 2014-11-14)
    Recent experimental studies have shown rich transition behaviour in rotating plane Couette ow (RPCF). In this paper we study the transition in supercritical RPCF theoretically by determination of equilibrium and periodic ...

  • Shearing waves and the MRI dynamo in stratified accretion discs 

    Donnelly, Cara (University of CambridgeDepartment of Applied Mathematics and Theoretical Physics, 2014-01-07)
    Accretion discs efficiently transport angular momentum by a wide variety of as yet imperfectly understood mechanisms, with profound implications for the disc lifetime and planet formation. We discuss two different methods ...

  • CLEANING OF VISCOUS DROPS ON A FLAT INCLINED SURFACE USING GRAVITY-DRIVEN FILM FLOWS 

    Landel, Julien R; McEvoy, Harry; Dalziel, Stuart Bruce (ElsevierFood and Bioproducts Processing, 2014-10-07)
    We investigate the fluid mechanics of cleaning viscous drops attached to a flat inclined surface using thin gravity-driven film flows. We focus on the case where the drop cannot be detached from the surface by the mechanical ...

  • Cleaning of Viscous Droplets on an Inclined Planar Surface Using Film Flows 

    Landel, JR; Thomas, AL; McEvoy, H; Dalziel, Stuart Bruce (Australian Fluids Mechanics SocietyProceedings of the Nineteenth Australasian Fluid Mechanics Conference, 2014)
    We investigate the fluid mechanics of cleaning viscous drops attached to a flat inclined surface using thin gravity-driven film flows. We focus on the case where the drop cannot be detached from the surface by the mechanical ...

  • Birational geometry of hypersurfaces in products of projective spaces 

    Ottem, John Christian (SpringerMathematische Zeitschrift, 2015)
    We study the birational properties of hypersurfaces in products of projective spaces. In the case of hypersurfaces in Pm x Pn, we describe their nef, movable and e ective cones and determine when they are Mori dream ...

  • Freezing colloidal suspensions: periodic ice lenses and compaction 

    Anderson, Anthony M; Worster, Michael Grae (CUP, 2014-10-14)
    Recent directional solidification experiments with aqueous suspensions of alumina particles (Anderson & Worster 2012) motivate a model for freezing colloidal suspensions that builds upon a theoretical framework developed ...

  • Modelling of partially-resolved oceanic symmetric instability 

    Bachman, Scott Daniel; Taylor, John Ryan (ElsevierOcean Modelling, 2014-08-04)
    A series of idealized numerical models have been developed to investigate the effects of partially resolved symmetric instability (SI) in oceanic general circulation models. An analysis of the energetics of symmetric instability ...

  • Noise generation by turbulence-propeller interaction in asymmetric flow 

    Robison, Rosalyn AV; Peake, Nigel (Cambridge University PressJournal of Fluid Mechanics, 2014)
    This paper is concerned with a particular source of both broadband and tonal aeroengine noise, termed Unsteady Distortion Noise (UDN). UDN arises from the interaction between turbulent eddies, which occur naturally in the ...

  • Zonally symmetric adjustment in the presence of artificial relaxation 

    Hitchcock, Adam Peter; Haynes, Peter Howard (American Meteorological SocietyJournal of the Atmospheric Sciences, 2014-06-15)
    Numerical experiments, presented in a companion paper, have been performed in which the zonal mean state of the stratosphere in a comprehensive, stratosphere-resolving, general circulation model is strongly relaxed (or ...