2004

最新文章

• Einstein metrics and complex singularities AI翻译
  作者：Calderbank, DMJ; Singer, MA
  作者单位：University of Edinburgh
  摘要：This paper is concerned with the construction of special metrics on non-compact 4-manifolds which arise as resolutions of complex orbifold singularities. Our study is close in spirit to the construction of the hyperkahler gravitational instantons, but we focus on a different class of singularities. We show that any resolution X of an isolated cyclic quotient singularity admits a complete scalar-flat Kahler metric (which is hyperkahler if and only if K-X is trivial), and that if K-X is strictly...
• Tate cohomology and periodic localization of polynomial functors AI翻译
  作者：Kuhn, NJ
  作者单位：University of Virginia
  摘要：In this paper, we show that Goodwillie calculus, as applied to functors from stable homotopy to itself, interacts in striking ways with chromatic aspects of the stable category. Localized at a fixed prime p, let T(n) be the telescope of a v(n) self map of a finite S-module of type n. The Periodicity Theorem of Hopkins and Smith implies that the Bousfield localization functor associated to T(n)(*) is independent of choices. Goodwillie's general theory says that to any homotopy functor F from S-...
• On the existence of collisionless equivariant minimizers for the classical n-body problem AI翻译
  作者：Ferrario, DL; Terracini, S
  作者单位：Polytechnic University of Milan; University of Milano-Bicocca
  摘要：We show that the minimization of the Lagrangian action functional on suitable classes of symmetric loops yields collisionless periodic orbits of the n-body problem, provided that some simple conditions on the symmetry group are satisfied. More precisely, we give a fairly general condition on symmetry groups G of the loop space Lambda for the n-body problem (with potential of homogeneous degree -alpha, with alpha>0) which ensures that the restriction of the Lagrangian action A to the space Lamb...
• On the holomorphic convexity of the linear reductive spaces of a complex projective algebraic manifold AI翻译
  作者：Eyssidieux, P
  作者单位：Universite de Toulouse; Universite Toulouse III - Paul Sabatier; Centre National de la Recherche Scientifique (CNRS)
  摘要：Let X be a smooth connected compact projective variety over C. We study the Shafarevich conjecture concerning holomorphic convexity along the lines of Kollaar's approach, when the fundamental group of X admits large finite dimensionnal representations. We prove that, given nis an element ofN, the topological covering space (X) over tilde (n) of a projective algebraic compact complex manifold X corresponding to the intersection of the kernels of all linear reductive representations of pi(1)(X) ...
• Propagation of singularities for the wave equation on conic manifolds AI翻译
  作者：Melrose, R; Wunsch, J
  作者单位：Northwestern University; Massachusetts Institute of Technology (MIT)
  摘要：For the wave equation associated to the Laplacian on a compact manifold with boundary with a conic metric (with respect to which the boundary is metrically a point) the propagation of singularities through the boundary is analyzed. Under appropriate regularity assumptions the diffracted, non-direct, wave produced by the boundary is shown to have Sobolev regularity greater than the incoming wave.
• Transport equation and Cauchy problem for BV vector fields AI翻译
  作者：Ambrosio, L
  作者单位：Scuola Normale Superiore di Pisa
• Numerical equivalence defined on Chow groups of Noetherian local rings AI翻译
  作者：Kurano, K
  作者单位：Meiji University
  摘要：In the present paper, we define a notion of numerical equivalence on Chow groups or Grothendieck groups of Noetherian local rings, which is an analogue of that on smooth projective varieties. Under a mild condition, it is proved that the Chow group modulo numerical equivalence is a finite dimensional Q-vector space, as in the case of smooth projective varieties. Numerical equivalence on local rings is deeply related to that on smooth projective varieties. For example, if Grothendieck's standar...
• On differentiability of SRB states for partially hyperbolic systems AI翻译
  作者：Dolgopyat, D
  作者单位：University System of Maryland; University of Maryland College Park
  摘要：Consider a one parameter family of diffeomorphisms f(epsilon) such that f(0) is an Anosov element in a standard abelian Anosov action having sufficiently strong mixing properties. Let nu(epsilon) be any u-Gibbs state for f(epsilon). We prove (Theorem 1) that for any C-infinity function A the map epsilon-->nu(epsilon)(A) is differentiable at epsilon=0. This implies (Corollary 2.2) that the difference of Birkhoff averages of the perturbed and unperturbed systems is proportional to epsilon. We ap...
• Equal sums of three powers AI翻译
  作者：Browning, TD; Heath-Brown, DR
  作者单位：University of Oxford
• A finite loop space not rationally equivalent to a compact Lie group AI翻译
  作者：Andersen, KKS; Bauer, T; Grodal, J; Pedersen, EK
  作者单位：Aarhus University; University of Munster; University of Chicago; State University of New York (SUNY) System; Binghamton University, SUNY
  摘要：We construct a connected finite loop space of rank 66 and dimension 1254 whose rational cohomology is not isomorphic as a graded vector space to the rational cohomology of any compact Lie group, hence providing a counterexample to a classical conjecture. Aided by machine calculation we verify that our counterexample is minimal, i.e., that any finite loop space of rank less than 66 is in fact rationally equivalent to a compact Lie group, extending the classical known bound of 5.