Department of Materials Science and Metallurgy: Recent submissions

Now showing items 361-380 of 648

  • Arctic Sea Ice Loss in Different Regions Leads to Contrasting Northern Hemisphere Impacts 

    McKenna, Christine; Bracegirdle, TJ; Shuckburgh, EF; Haynes, Peter Howard; Joshi, MM (Wiley-BlackwellGeophysical Research Letters, 2018-01-28)
    To explore the mechanisms linking Arctic sea-ice loss to changes in mid-latitude surface temperatures, we conduct idealized modeling experiments using an intermediate general circulation model and with sea-ice loss confined ...

  • A gluing operator for the ambitwistor string 

    Roehrig, KA; Skinner, David Benjamin
    We present a new operator in the ambitwistor string which glues together correlators with fewer points or of lower genus. It underpins the recursive construction of tree-level CHY scattering amplitudes by Dolan & Goddard, ...

  • Evolution of cyclic mixmaster universes with noncomoving radiation 

    Ganguly, C; Barrow, John David (American Physical SocietyPhysical Review D, 2017-12-15)
    We study a model of a cyclic, spatially homogeneous, anisotropic mixmaster universe of Bianchi type IX 'mixmaster' universe, containing the a radiation field with non-comoving ('tilted' with respect to the tetrad frame of ...

  • Evolution of cyclic mixmaster universes with noncomoving radiation 

    Barrow, John David; Ganguly, Chandrima
    We study a model of a cyclic, spatially homogeneous, anisotropic mixmaster universe of Bianchi type IX 'mixmaster' universe, containing the a radiation field with non-comoving ('tilted' with respect to the tetrad frame of ...

  • Is there a breakdown of effective field theory at the horizon of an extremal black hole? 

    Hadar, S; Reall, Harvey Stephen
    © 2017, The Author(s). Linear perturbations of extremal black holes exhibit the Aretakis instability, in which higher derivatives of a scalar field grow polynomially with time along the event horizon. This suggests that ...

  • On the hyperbolicity of the most general Horndeski theory 

    Papallo, Giuseppe (American Physical SocietyPHYSICAL REVIEW D, 2017-12-27)
    In this paper we study the hyperbolicity of the equations of motion for the most general Horndeski theory of gravity in a generic "weak field" background. We first show that a special case of this theory, namely Einstein ...

  • Cosmological models in energy-momentum-squared gravity 

    Board, CVR; Barrow, John David (American Physical SocietyPhysical Review D, 2017-12-15)
    We study the cosmological effects of adding terms of higher-order in the usual energy-momentum tensor to the matter lagrangian of general relativity. This is in contrast to most studies of higher-order gravity which focus ...

  • Quantum reality via late-time photodetection 

    Kent, Adrian Patrick (APSPhysical Review A, 2017-12-18)
    We further investigate postulates for realist versions of r elativistic quantum theory and quantum field theory in Minkowski space and other background space-t imes. According to these postulates, quantum theory is ...

  • Vortex-ring-induced stratified mixing: Mixing model 

    Olsthoorn, Jason; Dalziel, Stuart Bruce (Cambridge University PressJournal of Fluid Mechanics, 2018-02-25)
    The study of vortex-ring-induced mixing has been significant for understanding stratified turbulent mixing in the absence of a mean flow. Renewed interest in this topic has prompted the development of a one-dimensional ...

  • Bundling of elastic filaments induced by hydrodynamic interactions 

    Man, Yi; Page, W; Poole, RJ; Lauga, Eric Jean-Marie (Physical Review Fluids, 2017-12-01)
    Peritrichous bacteria swim in viscous fluids by rotating multiple helical flagellar filaments. As the bacterium swims forward, all its flagella rotate in synchrony behind the cell in a tight helical bundle. When the bacterium ...

  • Evidence for the Poisson/Gaudin--Mehta phase transition for band matrices on global scales 

    Swan, Andrew; Olver, Sheehan
    We prove that the Poisson/Gaudin--Mehta phase transition conjectured to occur when the bandwidth of an N ⨯ N symmetric band matrix grows like b = √N is naturally observable in the rate of convergence of the level density ...

  • Spontaneous oscillations of elastic filaments induced by molecular motors. 

    De Canio, Gabriele; Lauga, Eric Jean-Marie; Goldstein, Raymond Ethan (The Royal SocietyJournal of the Royal Society, Interface, 2017-11)
    It is known from the wave-like motion of microtubules in motility assays that the piconewton forces that motors produce can be sufficient to bend the filaments. In cellular phenomena such as cytosplasmic streaming, molecular ...

  • The grasshopper problem. 

    Goulko, Olga; Kent, Adrian Patrick (Royal Society of LondonProceedings. Mathematical, physical, and engineering sciences, 2017-11-22)
    We introduce and physically motivate the following problem in geometric combinatorics, originally inspired by analysing Bell inequalities. A grasshopper lands at a random point on a planar lawn of area 1. It then jumps ...

  • The emergence of shallow easterly jets within QBO westerlies 

    Hitchcocka, P; Haynes, Peter Howard; Randel, WJ; Birner, T (Journal of the Atmospheric Sciences, 2018-01-01)
    © 2018 American Meteorological Society. A configuration of an idealized general circulation model has been obtained in which a deep, stratospheric, equatorial, westerly jet is established that is spontaneously and ...

  • Symmetries and geometrical properties of dynamical fluctuations in molecular dynamics 

    Jack, Robert Logan; Kaiser, M; Zimmer, J (Entropy, 2017-10-01)
    We describe some general results that constrain the dynamical fluctuations that can occur in non-equilibrium steady states, with a focus on molecular dynamics. That is, we consider Hamiltonian systems, coupled to external ...

  • Aerodynamic noise from rigid trailing edges with finite porous extensions 

    Kisil, Anastasia; Ayton, Lorna Jane (Cambridge University PressJournal of Fluid Mechanics, 2018-02-10)
    This paper investigates the effects of finite flat porous extensions to semi-infinite impermeable flat plates in an attempt to control trailing-edge noise through bio-inspired adaptations. Specifically the problem of sound ...

  • An Iterative Wiener--Hopf method for triangular matrix functions with exponential factors 

    Kisil, Anastasia
    This paper introduces a new method for constructing approximate solutions to a class of Wiener{Hopf equations. This is particularly useful since exact solutions of this class of Wiener{Hopf equations, at the moment, cannot ...

  • Does a Growing Static Length Scale Control the Glass Transition? 

    Wyart, Matthieu; Cates, Michael Elmhirst (Physical review letters, 2017-11-09)
    Several theories of the glass transition propose that the structural relaxation time is controlled by a growing static length scale that is determined by the free energy landscape but not by the local dynamical rules ...

  • Spatiotemporal Self-Organization of Fluctuating Bacterial Colonies. 

    Grafke, Tobias; Cates, Michael Elmhirst; Vanden-Eijnden, Eric (APSPhysical review letters, 2017-11-03)
    We model an enclosed system of bacteria, whose motility-induced phase separation is coupled to slow population dynamics. Without noise, the system shows both static phase separation and a limit cycle, in which a rising ...

  • Stability analysis for n -periodic arrays of fluid systems 

    Schmid, PJ; De Pando, MF; Peake, Nigel (Physical Review Fluids, 2017-11-01)
    © 2017 American Physical Society. A computational framework is proposed for the linear modal and nonmodal analysis of fluid systems consisting of a periodic array of n identical units. A formulation in either time or ...