Department of Pure Mathematics and Mathematical Statistics (DPMMS): Recent submissions

Now showing items 161-180 of 248

  • Cohomology of automorphism groups of free groups with twisted coefficients 

    Randal-Williams, Oscar
    We compute the groups H*(Aut(F$_{n}$);M) and H*(Out(F$_{n}$);M) in a stable range, where M is obtained by applying a Schur functor to H$_{Q}$ or H$_{Q}$, respectively the first rational homology and cohomology of F$_{n}$. ...

  • Bayesian Nonparametric Ordination for the Analysis of Microbial Communities 

    Ren, Boyu; Bacallado, Sergio; Favaro, Stefano; Holmes, Susan; Trippa, Lorenzo (Taylor & FrancisJournal of the American Statistical Association, 2017-07-10)
    Human microbiome studies use sequencing technologies to measure the abundance of bacterial species or Operational Taxonomic Units (OTUs) in samples of biological material. Typically the data are organized in contingency ...

  • Infinite loop spaces and positive scalar curvature 

    Botvinnik, B; Ebert, J; Randal-Williams, Oscar (SpringerInventiones Mathematicae, 2017-09-01)
    We study the homotopy type of the space of metrics of positive scalar curvature on high-dimensional compact spin manifolds. Hitchin used the fact that there are no harmonic spinors on a manifold with positive scalar curvature ...

  • Homological stability for moduli spaces of high dimensional manifolds. II 

    Galatius, S; Randal-Williams, Oscar
    We prove a homological stability theorem for moduli spaces of manifolds of dimension 2$\textit{n}$, for attaching handles of index at least $\textit{n}$, after these manifolds have been stabilised by countably many copies ...

  • 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 ...

  • Four-Dimensional Weakly Self-avoiding Walk with Contact Self-attraction 

    Bauerschmidt, Roland; Slade, G; Wallace, BC (SpringerJournal of Statistical Physics, 2017-04-01)
    We consider the critical behaviour of the continuous-time weakly self-avoiding walk with contact self-attraction on $\mathbb{Z}$$^{4}$, for sufficiently small attraction. We prove that the susceptibility and correlation ...

  • Random-projection ensemble classification 

    Cannings, Timothy Ivor; Samworth, Richard John
    We introduce a very general method for high-dimensional classification, based on careful combination of the results of applying an arbitrary base classifier to random projections of the feature vectors into a lower-dimensional ...

  • Elliptic curves over Q$_{∞}$ are modular 

    Thorne, Jack Arfon
    We show that if $\textit{p}$ is a prime, then all elliptic curves de ned over the cyclotomic $\mathbb{Z}$$_{p}$-extension of Q are modular.

  • Connective constants and height functions for Cayley graphs 

    Grimmett, Geoffrey Richard; Li, Z (American Mathematical SocietyTransactions of the American Mathematical Society, 2017-03-31)
    The connective constant $μ$($G$) of an infinite transitive graph $G$ is the exponential growth rate of the number of self-avoiding walks from a given origin. In earlier work of Grimmett and Li, a locality theorem was proved ...

  • K-stability for Kähler manifolds 

    Dervan, Ruadhai; Ross, Julius Andrew (International PressMathematical Research Letters, 2017-09)
    We formulate a notion of K-stability for Kähler manifolds, and prove one direction of the Yau–Tian–Donaldson conjecture in this setting. More precisely, we prove that the Mabuchi functional being bounded below (resp. ...

  • On the GL$_{n}$-eigenvariety and a conjecture of Venkatesh 

    Hansen, D; Thorne, Jack Arfon
    Let π be a cuspidal, cohomological automorphic representation of GL$_{n}$(A). Venkatesh has suggested that there should exist a natural action of the exterior algebra of a certain motivic cohomology group on the π-part of ...

  • Infinitely many monotone Lagrangian tori in del Pezzo surfaces 

    Ferreira de Velloso Vianna, Renato
    We construct almost toric fibrations (ATFs) on all del Pezzo surfaces, endowed with a monotone symplectic form. Except for CP$^{2}$#CP$^{2}$, CP$^{2}$#2CP$^{2}$, we are able to get almost toric base diagrams (ATBDs) of ...

  • The Planar Ising Model and Total Positivity 

    Lis, Marcin (SpringerJournal of Statistical Physics, 2017-01-01)
    A matrix is called totally positive (resp. totally nonnegative) if all its minors are positive (resp. nonnegative). Consider the Ising model with free boundary conditions and no external field on a planar graph G. Let ...

  • Derivative of the standard $p$-adic $L$-function associated with a Siegel form 

    Rosso, Giovanni
    In this paper we construct a two variables p-adic L-function for the standard representation associated with a Hida family of parallel weight genus g Siegel forms, using a method previously developed by B\"ocherer--Schmidt ...

  • Shadows of Teichmüller Discs in the Curve Graph 

    Tang, R; Webb, Richard Charles
    We consider several natural sets of curves associated to a given Teichmüller disc, such as the systole set or cylinder set, and study their coarse geometry inside the curve graph. We prove that these sets are quasiconvex ...

  • An upper bound for the pseudoisotopy stable range 

    Randal-Williams, Oscar (SpringerMathematische Annalen, 2017-08-01)
    We prove that the pseudoisotopy stable range for manifolds of dimension 2n can be no better than (2n - 2). In order to do so, we define new characteristic classes for block bundles, extending our earlier work with Ebert, ...

  • Teichmüller spaces and bounded symmetric domains do not mix isometrically 

    Antonakoudis, Stergios (SpringerGeometric and Functional Analysis, 2017-06-01)
    This paper shows that, in dimensions two or more, there are no holomorphic isometries between Teichüller spaces and bounded symmetric domains in their intrinsic Kobayashi metric.

  • Tautological rings for high-dimensional manifolds 

    Galatius, S; Grigoriev, I; Randal-Williams, Oscar (Cambridge University PressCompositio Mathematica, 2017-04)
    We study tautological rings for high-dimensional manifolds, that is, for each smooth manifold $M$ the ring $R^*$($M$) of those characteristic classes of smooth fibre bundles with fibre $M$ which is generated by generalised ...

  • Pairwise Markov properties for regression graphs 

    Sadeghi, Kayvan; Wermuth, N (WileyStat, 2016-11-13)
    With a sequence of regressions, one may generate joint probability distributions. One starts with a joint, marginal distribution of context variables having possibly a concentration graph structure and continues with an ...

  • Radically filtered quasi-hereditary algebras and rigidity of tilting modules 

    HAZI, Amit (Cambridge University PressMathematical Proceedings of the Cambridge Philosophical Society, 2017-09)
    Let $\textit{A}$ be a quasi-hereditary algebra. We prove that in many cases, a tilting module is rigid (i.e. has identical radical and socle series) if it does not have certain subquotients whose composition factors extend ...