3期

最新文章

• Faithful actions of the absolute Galois group on connected components of moduli spaces AI翻译
  作者：Bauer, Ingrid; Catanese, Fabrizio; Grunewald, Fritz
  作者单位：University of Bayreuth
  摘要：We use a canonical procedure associating to an algebraic number a first a hyperelliptic curve C-a, and then a triangle curve (D-a, G(a)) obtained through the normal closure of an associated Belyi function. In this way we show that the absolute Galois group Gal((Q) over bar /Q) acts faithfully on the set of isomorphism classes of marked triangle curves, and on the set of connected components of marked moduli spaces of surfaces isogenous to a higher product (these are the free quotients of a pro...
• Expansion of random graphs: new proofs, new results AI翻译
  作者：Puder, Doron
  作者单位：Hebrew University of Jerusalem
  摘要：We present a new approach to showing that random graphs are nearly optimal expanders. This approach is based on recent deep results in combinatorial group theory. It applies to both regular and irregular random graphs. Let be a random -regular graph on vertices, and let be the largest absolute value of a non-trivial eigenvalue of its adjacency matrix. It was conjectured by Alon (Combinatorica 6(2), 83-96, 1986) that a random -regular graph is almost Ramanujan, in the following sense: for every...
• Stability in the homology of congruence subgroups AI翻译
  作者：Putman, Andrew
  作者单位：Rice University
  摘要：The homology groups of many natural sequences of groups {G(n)}(n=1)(infinity) (e.g. general linear groups, mapping class groups, etc.) stabilize as n -> infinity. Indeed, there is a well-known machine for proving such results that goes back to early work of Quillen. Church and Farb discovered that many sequences of groups whose homology groups do not stabilize in the classical sense actually stabilize in some sense as representations. They called this phenomena representation stability. We pro...
• Kahler currents and null loci AI翻译
  作者：Collins, Tristan C.; Tosatti, Valentino
  作者单位：Harvard University; Northwestern University
  摘要：We prove that the non-Kahler locus of a nef and big class on a compact complex manifold bimeromorphic to a Kahler manifold equals its null locus. In particular this gives an analytic proof of a theorem of Nakamaye and Ein-Lazarsfeld-Musta-Nakamaye-Popa. As an application, we show that finite time non-collapsing singularities of the Kahler-Ricci flow on compact Kahler manifolds always form along analytic subvarieties, thus answering a question of Feldman-Ilmanen-Knopf and Campana. We also exten...
• Integrable systems, toric degenerations and Okounkov bodies AI翻译
  作者：Harada, Megumi; Kaveh, Kiumars
  作者单位：McMaster University; Pennsylvania Commonwealth System of Higher Education (PCSHE); University of Pittsburgh
  摘要：Let X be a smooth projective variety of dimension n over C equipped with a very ample Hermitian line bundle L. In the first part of the paper, we show that if there exists a toric degeneration of X satisfying some natural hypotheses (which are satisfied in many settings), then there exists a surjective continuous map from X to the special fiber X-0 which is a symplectomorphism on an open dense subset U. From this we are then able to construct a completely integrable system on X in the sense of...
• Moments and distribution of central L-values of quadratic twists of elliptic curves AI翻译
  作者：Radziwill, Maksym; Soundararajan, K.
  作者单位：Institute for Advanced Study - USA; Stanford University
  摘要：We show that if one can compute a little more than a particular moment for some family of L-functions, then one has upper bounds of the conjectured order of magnitude for all smaller (positive, real) moments and a one-sided central limit theorem holds. We illustrate our method for the family of quadratic twists of an elliptic curve, obtaining sharp upper bounds for all moments below the first. We also establish a one sided central limit theorem supporting a conjecture of Keating and Snaith. Ou...
• Operator renewal theory and mixing rates for dynamical systems with infinite measure (vol 189, pg 61, 2012) AI翻译
  作者：Melbourne, Ian; Terhesiu, Dalia
  作者单位：University of Warwick; University of Vienna
• Whitney-Holder continuity of the SRB measure for transversal families of smooth unimodal maps AI翻译
  作者：Baladi, Viviane; Benedicks, Michael; Schnellmann, Daniel
  作者单位：University of Copenhagen; Royal Institute of Technology; Centre National de la Recherche Scientifique (CNRS); CNRS - National Institute for Mathematical Sciences (INSMI); Universite PSL; Ecole Normale Superieure (ENS)
  摘要：We consider families of nondegenerate unimodal maps. We study the absolutely continuous invariant probability (SRB) measure of , as a function of on the set of Collet-Eckmann (CE) parameters: Upper bounds: Assuming existence of a transversal CE parameter, we find a positive measure set of CE parameters , and, for each , a set of polynomially recurrent parameters containing as a Lebesgue density point, and constants , , so that, for every -Holder function , In addition, for all , the renormalis...