2011

最新文章

• Orbit inequivalent actions for groups containing a copy of F2 AI翻译
  作者：Ioana, Adrian
  作者单位：California Institute of Technology
  摘要：We prove that if a countable group Gamma contains a copy of F-2, then it admits uncountably many non orbit equivalent actions.
• On derivatives of Artin L-series AI翻译
  作者：Burns, David
  作者单位：University of London; King's College London
  摘要：We present a universal theory of refined Stark conjectures. We give evidence in support of these explicit and very general conjectures, including a full proof in several important cases, and explain the connection to previous conjectures of Bloch and Kato, of Lichtenbaum and of Serre and Tate. We also deduce a wide range of unconditional consequences of these results concerning the annihilation, as Galois modules, of ideal class groups by explicit elements constructed from the values of higher...
• C2 surface diffeomorphisms have symbolic extensions AI翻译
  作者：Burguet, David
  作者单位：Universite Paris Saclay
  摘要：We prove that C-2 surface diffeomorphisms have symbolic extensions, i.e. topological extensions which are subshifts over a finite alphabet. Following the strategy of Downarowicz and Maass (Invent. Math. 176: 617-636, 2009) we bound the local entropy of ergodic measures in terms of Lyapunov exponents. This is done by reparametrizing Bowen balls by contracting maps in a approach combining hyperbolic theory and Yomdin's theory.
• Speed of Arnold diffusion for analytic Hamiltonian systems AI翻译
  作者：Zhang, Ke
  作者单位：University of Toronto
  摘要：For a convex, real analytic, epsilon-close to integrable Hamiltonian system with n >= 5 degrees of freedom, we construct an orbit exhibiting Arnold diffusion with the diffusion time bounded by exp(C epsilon (-1/2(n-2))). This upper bound of the diffusion time almost matches the lower bound of order exp(epsilon (-1/2(n-1))) predicted by the Nekhoroshev-type stability results. Our method is based on the variational approach of Bessi and Mather, and includes a new construction on the space of fre...
• Even Galois representations and the Fontaine-Mazur conjecture AI翻译
  作者：Calegari, Frank
  作者单位：Northwestern University
  摘要：We prove, under mild hypotheses, that there are no irreducible two-dimensional ordinary even Galois representations of Gal((Q) over bar /Q) with distinct Hodge-Tate weights. This is in accordance with the Fontaine-Mazur conjecture. If K/Q is an imaginary quadratic field, we also prove ( again, under certain hypotheses) that Gal((Q) over bar /K) does not admit irreducible two-dimensional ordinary Galois representations of non-parallel weight.
• The Jacobian determinant revisited AI翻译
  作者：Brezis, Haim; Nguyen, Hoai-Minh
  作者单位：Rutgers University System; Rutgers University New Brunswick; Technion Israel Institute of Technology; New York University
• Special cycles on unitary Shimura varieties I. Unramified local theory AI翻译
  作者：Kudla, Stephen; Rapoport, Michael
  作者单位：University of Bonn; University of Toronto
  摘要：The supersingular locus in the fiber at p of a Shimura variety attached to a unitary similitude group GU(1, n - 1) over Q is uniformized by a formal scheme N. In the case when p is an inert prime, we define special cycles Z(x) in N, associated to collections x of m 'special homomorphisms' with fundamental matrix T is an element of Herm(m)(O-k). When m = n and T is nonsingular, we show that the cycle Z(x) is either empty or is a union of components of the Ekedahl-Oort stratification, and we giv...
• A proof of the uniform boundedness of solutions to the wave equation on slowly rotating Kerr backgrounds AI翻译
  作者：Dafermos, Mihalis; Rodnianski, Igor
  作者单位：Princeton University; University of Cambridge
  摘要：We consider Kerr spacetimes with parameters a and M such that vertical bar a vertical bar << M, Kerr-Newman spacetimes with parameters vertical bar Q vertical bar << M, vertical bar a vertical bar << M and more generally, stationary axisymmetric black hole exterior spacetimes (M, g) which are sufficiently close to a Schwarzschild metric with parameter M > 0 and whose Killing fields span the null generator of the event horizon. We show uniform boundedness on the exterior for solutions to the wa...
• K-theoretic rigidity and slow dimension growth AI翻译
  作者：Toms, Andrew
  作者单位：Purdue University System; Purdue University
  摘要：Let A be an approximately subhomogeneous (ASH) C*-algebra with slow dimension growth. We prove that if A is unital and simple, then the Cuntz semigroup of A agrees with that of its tensor product with the Jiang-Su algebra (sic). In tandem with a result of W. Winter, this yields the equivalence of (sic)-stability and slow dimension growth for unital simple ASH algebras. This equivalence has several consequences, including the following classification theorem: unital ASH algebras which are simpl...
• Intersection theory on Shimura surfaces II AI翻译
  作者：Howard, Benjamin
  作者单位：Boston College
  摘要：This is the third of a series of papers relating intersections of special cycles on the integral model of a Shimura surface to Fourier coefficients of Hilbert modular forms. More precisely, we embed the Shimura curve over ae associated to a rational quaternion algebra into the Shimura surface associated to the base change of the quaternion algebra to a real quadratic field. After extending the associated moduli problems over acurrency sign we obtain an arithmetic threefold with a embedded arit...