Browsing Department of Pure Mathematics and Mathematical Statistics (DPMMS) by Title

Now showing items 229-248 of 248

  • TORSION GALOIS REPRESENTATIONS OVER CM FIELDS AND HECKE ALGEBRAS IN THE DERIVED CATEGORY 

    Newton, James; Thorne, Jack Arfon (Cambridge University PressForum of Mathematics, Sigma, 2016-07-21)
    We construct algebras of endomorphisms in the derived category of the cohomology of arithmetic manifolds, which are generated by Hecke operators. We construct Galois representations with coefficients in these Hecke algebras ...

  • Total Positivity in Markov Structures 

    Fallat, S; Lauritzen, S; Sadeghi, Kayvan; Uhler, C; Wermuth, N; Zwiernik, K (Institute of Mathematical StatisticsAnnals of Statistics, 2017-06)
    We discuss properties of distributions that are multivariate totally positive of order two (MTP$_{2}$) related to conditional independence. In particular, we show that any independence model generated by an MTP$_{2}$ ...

  • Towards Automatic Model Comparison: An Adaptive Sequential Monte Carlo Approach 

    Zhou, Yan; Johansen, Adam M; Aston, John Alexander (Taylor & FrancisJournal of Computational and Graphical Statistics, 2015-08-17)
    Model comparison for the purposes of selection, averaging and validation is a problem found throughout statistics. Within the Bayesian paradigm, these problems all require the calculation of the posterior probabilities of ...

  • Towards mirror symmetry for varieties of general type 

    Gross, Mark William; Katzarkov, Ludmil; Ruddat, Helge (ElsevierAdvances in Mathematics, 2016)

  • Trading to stops 

    Imkeller, Nora; Rogers, Leonard Christopher (Society for Industrial and Applied MathematicsSiam Journal on Financial Mathematics, 2014-12-16)
    The use of trading stops is a common practice in financial markets for a variety of reasons: it reduces the frequency of trading and thereby transaction costs; it provides a simple way to control losses on a given trade, ...

  • Transversals as Generating Sets in Finitely Generated Groups 

    Button, Jack; Chiodo, Maurice Charles; Laris, Mariano Zeron-Medina (Cambridge University PressBulletin of the Australian Mathematical Society, 2015-08-19)
    We explore transversals of finite index subgroups of finitely generated groups. We show that when H is a subgroup of a rank n group G and H has index at least n in G then we can construct a left transversal for H which ...

  • Trend to equilibrium for the Becker–Döring equations: an analogue of Cercignani's conjecture 

    Cañizo, JA; Einav, Amit; Lods, B (Mathematical Sciences PublishersAnalysis and PDE, 2017-08-01)
    We investigate the rate of convergence to equilibrium for subcritical solutions to the Becker–Döring equations with physically relevant coagulation and fragmentation coefficients and mild assumptions on the given initial ...

  • Trust in numbers 

    Spiegelhalter, David John (WileyJournal of the Royal Statistical Society. Series A: Statistics in Society, 2017-10-01)
    Those who value quantitative and scientific evidence are faced with claims both of a reproducibility crisis in scientific publication, and of a post-truth society abounding in fake news and alternative facts. Both issues ...

  • Tubular free by cyclic groups act freely on CAT(0) cube complexes 

    Button, Jack (Canadian Mathematical SocietyCanadian Mathematical Bulletin, 2017-03-01)
    We identify when a tubular group (the fundamental group of a finite graph of groups with $\mathbb{Z}$$^{2}$ vertex and $\mathbb{Z}$ edge groups) is free by cyclic and show, using Wise's equitable sets criterion, that every ...

  • Turán-type results for complete h-partite graphs in comparability and incomparability graphs 

    Tomon, István (SpringerOrder, 2015-01-05)
    We consider an h-partite version of Dilworth's theorem with multiple partial orders. Let P be a fi nite set, and let <₁, ..., <ᵣ be partial orders on P. Let G(P, <₁, ..., <ᵣ) be the graph whose vertices are the elements ...

  • Two topics in financial mathematics : Forward utility and consumption functions & Hedging with variance swaps in infinite dimensions 

    Berrier, Francois (University of CambridgeDepartment of Pure Mathematics and Mathematical Statistics, 2010-10)
    Financial Mathematics is often presented as being composed of two main branches: one dealing with investment and consumption, with the aim of answering the now ancient question of how people should invest and spend their ...

  • Type theoretic weak factorization systems 

    North, Paige Randall (University of CambridgeDepartment of Pure Mathematics and Mathematical StatisticsKing's, 2017-06-01)
    This thesis presents a characterization of those categories with weak factorization systems that can interpret the theory of intensional dependent type theory with Σ, Π, and identity types. We use display map categories ...

  • Undecidability and the developability of permutoids and rigid pseudogroups 

    Bridson, MR; Wilton, Henry John (Cambridge University PressForum of Mathematics, Sigma, 2017-03-20)
    A $\textit{permutoid}$ is a set of partial permutations that contains the identity and is such that partial compositions, when defined, have at most one extension in the set. In 2004 Peter Cameron conjectured that there ...

  • Uniform Bounds for Black--Scholes Implied Volatility 

    Tehranchi, Michael Rummine (Society for Industrial and Applied MathematicsSIAM Journal on Financial Mathematics, 2016-11-29)
    In this note, Black--Scholes implied volatility is expressed in terms of various optimization problems. From these representations, upper and lower bounds are derived which hold uniformly across moneyness and call price. ...

  • Uniform Stability of Twisted Constant Scalar Curvature Kähler Metrics 

    Dervan, Ruadhai (Oxford University PressInternational Mathematics Research Notices, 2015-10-14)
    We introduce a norm on the space of test configurations, called the minimum norm. We conjecture that uniform K-stability is equivalent to the existence of a constant scalar curvature Kähler metric. This uniformity is ...

  • Unifying Amplitude and Phase Analysis Unifying Amplitude and Phase Analysis. A Compositional Data Approach to Functional Multivariate Mixed-Effects Modeling of Mandarin Chinese 

    Hadjipantelis, PZ; Aston, John Alexander; Müller, HG; Evans, JP (Taylor & FrancisJournal of the American Statistical Association, 2015-07-06)
    Mandarin Chinese is characterized by being a tonal language; the pitch (or F0) of its utterances carries considerable linguistic information. However, speech samples from different individuals are subject to changes in ...

  • Unipotent elements in algebraic groups 

    Clarke, Matthew Charles (University of CambridgeDepartment of Pure Mathematics and Mathematical Statistics, 2012-01-10)
    This thesis is concerned with three distinct, but closely related, research topics focusing on the unipotent elements of a connected reductive algebraic group G, over an algebraically closed field k, and nilpotent elements ...

  • Unstable mode solutions to the Klein-Gordon equation in Kerr-anti-de Sitter spacetimes 

    Dold, Dominic (SpringerCommunications in Mathematical Physics, 2016)
    For any cosmological constant Λ = −3/$l^2$ < 0 and any $\alpha$ < 9/4, we find a Kerr-AdS spacetime ($M$, $g_{KAdS}$), in which the Klein-Gordon equation $\square g_{KAdS}$ ψ+$\alpha$/$l^2$ψ = 0 has an exponentially growing ...

  • Variation of Gieseker moduli spaces via quiver GIT 

    Greb, Daniel; Ross, Julius Andrew; Toma, Matei (Mathematical Sciences PublishersGeometry & Topology, 2016)
    We introduce a notion of stability for sheaves with respect to several polarisations that generalises the usual notion of Gieseker-stability. We prove, under a boundedness assumption, which we show to hold on threefolds ...

  • Witt groups of complex varieties 

    Zibrowius, Marcus (University of CambridgeDepartment of Pure Mathematics and Mathematical StatisticsTrinity Hall, 2011-07-12)
    The thesis Witt Groups of Complex Varieties studies and compares two related cohomology theories that arise in the areas of algebraic geometry and topology: the algebraic theory of Witt groups, and real topological K-theory. ...