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作者：Ionel, EN; Parker, TH
摘要：We define relative Gromov-Witten invariants of a symplectic manifold relative to a codimension-two symplectic submanifold. These invariants are the key ingredients in the symplectic sum formula of [IP4]. The main step is the construction of a compact space of 'V-stable' maps. Simple special cases include the Hurwitz numbers for algebraic curves and the enumerative invariants of Caporaso and Harris.
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作者：Mosher, L; Sageev, M; Whyte, K
摘要：Given a bounded valence, bushy tree T, we prove that any cobounded quasi-action of a group G on T is quasiconjugate to an action of G on another bounded valence, bushy tree T'. This theorem has many applications: quasi-isometric rigidity for fundamental groups of finite, bushy graphs of coarse PD(n) groups for each fixed n; a generalization to actions on Cantor sets of Sullivan's theorem about uniformly quasiconformal actions on the 2-sphere; and a characterization of locally compact topologic...
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作者：Carlen, EA; Gangbo, W
摘要：We study several constrained variational problems in the 2-Wasserstein metric for which the set of probability densities satisfying the constraint is not closed. For example, given a probability density F-0 on R-d and a time-step h > 0, we seek to minimize I(F) = hS(F)+W-2(2)(F-0,F) over-all of the probability densities F that have the same mean and variance as F-0, where S(F) is the entropy of F. We prove existence of minimizers. We also analyze the induced geometry of the set of densities sa...
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作者：Faber, C; Pandharipande, R
摘要：We prove a closed formula for integrals of the cotangent line classes against the top Chern class of the Hodge bundle on the moduli space of stable pointed curves. These integrals are computed via relations obtained from virtual localization in Gromov-Witten theory. An analysis of several natural matrices indexed by partitions is required.
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作者：Killip, R; Simon, B
摘要：We discuss the proof of and systematic application of Case's sum rules for Jacobi matrices. Of special interest is a linear combination of two of his sum rules which has strictly positive terms. Among our results are a complete classification of the spectral measures of all Jacobi matrices J for which J - J(0) is Hilbert-Schmidt, and a proof of Nevai's conjecture that the Szego condition holds if J - J(0) is trace class.
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作者：Biss, DK
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作者：Dranishnikov, AN; Ferry, SC; Weinberger, S
摘要：For each k is an element of Z, we construct a uniformly contractible metric on Euclidean space which is not mod k hypereuclidean. We also construct a pair of uniformly contractible Riemannian metrics on R-n, n greater than or equal to 11, so that the resulting manifolds Z and Z' are bounded homotopy equivalent by a homotopy equivalence which is not boundedly close to a homeomorphism. We show that for these spaces the C*-algebra assembly map K-*(lf) (Z) --> K-* (C* (Z)) from locally finite K-ho...
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作者：Heitmann, RC
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作者：Isaacs, IM; Navarro, G
摘要：Let G be an arbitrary finite group and fix a prime number p. The McKay conjecture asserts that G and the normalizer in G of a S, low p-subgroup have equal numbers of irreducible characters with degrees not divisible by p. The Alperin-McKay conjecture is version of this as applied to individual Brauer p-blocks of G. We offer evidence that perhaps much stronger forms of both of these conjectures are true.
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作者：Alexeev, V
摘要：I prove the existence, and describe the structure, of moduli space of pairs (P, Theta) consisting of a projective variety P with semiabelian group action and an ample Cartier divisor on it satisfying a few simple conditions. Every connected component of this moduli space is proper. A component containing a projective toric variety is described by a configuration of several polytopes, the main one of which is the secondary polytope. On the other hand, the component containing a principally pola...
