2007

最新文章

• Hida families and rational points on elliptic curves AI翻译
  作者：Bertolini, Massimo; Darmon, Henri
  作者单位：University of Milan; McGill University
• The Bogomolov conjecture for totally degenerate abelian varieties AI翻译
  作者：Gubler, Walter
  作者单位：Dortmund University of Technology
  摘要：We prove the Bogomolov conjecture for a totally degenerate abelian variety A over a function field. We adapt Zhang's proof of the number field case replacing the complex analytic tools by tropical analytic geometry. A key step is the tropical equidistribution theorem for A at the totally degenerate place v. As a corollary, we obtain finiteness of torsion points with coordinates in the maximal unramified algebraic extension over v.
• On the classification of simple inductive limit C*-algebras, II: The isomorphism theorem AI翻译
  作者：Elliott, George A.; Gong, Guihua; Li, Liangqing
  作者单位：University of Toronto; Hebei Normal University; University of Puerto Rico; University of Puerto Rico Rio Piedras
  摘要：In this article, it is proved that the invariant consisting of the scaled ordered K-group and the space of tracial states, together with the natural pairing between them, is a complete invariant for the class of unital simple C*-algebras which can be expressed as the inductive limit of a sequence A(1) -> A(2) -> ... -> A(n) -> ... with /A(n) = circle plus(tn)(i=1) Pn,iM[n,i](C(X-n,X-i))P-n,P-i, where X (n,i) is a compact metrizable space and P (n,i) is a projection in M-[n,M-i](C(X (n,i) )) fo...
• A Skolem-Mahler-Lech theorem in positive characteristic and finite automata AI翻译
  作者：Derksen, Harm
  作者单位：University of Michigan System; University of Michigan
  摘要：Lech proved in 1953 that the set of zeroes of a linear recurrence sequence in a field of characteristic 0 is the union of a finite set and finitely many infinite arithmetic progressions. This result is known as the Skolem-Mahler-Lech theorem. Lech gave a counterexample to a similar statement in positive characteristic. We will present some more pathological examples. We will state and prove a correct analog of the Skolem-Mahler-Lech theorem in positive characteristic. The zeroes of a recurrenc...
• Deconstructing Hopf spaces AI翻译
  作者：Castellana, Natalia; Crespo, Juan A.; Scherer, Jerome
  作者单位：Autonomous University of Barcelona; Universidad Carlos III de Madrid
  摘要：We characterize Hopf spaces with finitely generated cohomology as an algebra over the Steenrod algebra. We deconstruct the original space into an H-space Y with finite mod p cohomology and a finite number of p-torsion Eilenberg-Mac Lane spaces. We give a precise description of homotopy commutative H-spaces in this setting.
• A functorial construction of moduli of sheaves AI翻译
  作者：Alvarez-Consul, Luis; King, Alastair
  作者单位：Consejo Superior de Investigaciones Cientificas (CSIC); CSIC - Instituto de Ciencias Matematicas (ICMAT); University of Bath
  摘要：We show how natural functors from the category of coherent sheaves on a projective scheme to categories of Kronecker modules can be used to construct moduli spaces of semistable sheaves. This construction simplifies or clarifies technical aspects of existing constructions and yields new simpler definitions of theta functions, about which more complete results can be proved.
• Finiteness properties of arithmetic groups over function fields AI翻译
  作者：Bux, Kai-Uwe; Wortman, Kevin
  作者单位：University of Virginia; Yale University
  摘要：We determine when an arithmetic subgroup of a reductive group defined over a global function field is of type FP infinity by comparing its largescale geometry to the large-scale geometry of lattices in real semisimple Lie groups.
• Knot Floer homology detects fibred knots AI翻译
  作者：Ni, Yi
  作者单位：Princeton University
  摘要：Ozsvath and Szabo conjectured that knot Floer homology detects fibred knots in S-3. We will prove this conjecture for null-homologous knots in arbitrary closed 3-manifolds. Namely, if K is a knot in a closed 3-manifold Y, Y - K is irreducible, and (HFK) over cap (Y, K) is monic, then K is fibred. The proof relies on previous works due to Gabai, Ozsvath-Szabo, Ghiggini and the author. A corollary is that if a knot in S-3 admits a lens space surgery, then the knot is fibred.
• Integral Grothendieck-Riemann-Roch theorem AI翻译
  作者：Pappas, Georgios
  作者单位：Michigan State University
  摘要：We show that, in characteristic zero, the obvious integral version of the Grothendieck-Riemann-Roch formula obtained by clearing the denominators of the Todd and Chern characters is true (without having to divide the Chow groups by their torsion subgroups). The proof introduces an alternative to Grothendieck's strategy: we use resolution of singularities and the weak factorization theorem for birational maps.
• The characteristic class and ramification of an l-adic etale sheaf AI翻译
  作者：Abbes, Ahmed; Saito, Takeshi
  作者单位：Universite Paris 13; Centre National de la Recherche Scientifique (CNRS); University of Tokyo
  摘要：We introduce the characteristic class of an l-adic etale sheaf using a cohomological pairing due to Verdier (SGA5). As a consequence of the Lefschetz-Verdier trace formula, its trace computes the Euler-Poincare characteristic of the sheaf. We compare the characteristic class to two other invariants arising from ramification theory. One is the Swan class of Kato-Saito [17] and the other is the 0-cycle class defined by Kato for rank 1 sheaves in [16].