25,115 research outputs found

    Lower Bounds for On-line Interval Coloring with Vector and Cardinality Constraints

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    We propose two strategies for Presenter in the on-line interval graph coloring games. Specifically, we consider a setting in which each interval is associated with a dd-dimensional vector of weights and the coloring needs to satisfy the dd-dimensional bandwidth constraint, and the kk-cardinality constraint. Such a variant was first introduced by Epstein and Levy and it is a natural model for resource-aware task scheduling with dd different shared resources where at most kk tasks can be scheduled simultaneously on a single machine. The first strategy forces any on-line interval coloring algorithm to use at least (5m3)dlogd+3(5m-3)\frac{d}{\log d + 3} different colors on an m(dk+logd+3)m(\frac{d}{k} + \log{d} + 3)-colorable set of intervals. The second strategy forces any on-line interval coloring algorithm to use at least 5m2dlogd+3\lfloor\frac{5m}{2}\rfloor\frac{d}{\log d + 3} different colors on an m(dk+logd+3)m(\frac{d}{k} + \log{d} + 3)-colorable set of unit intervals

    Subelliptic SpinC Dirac Operators, IV Proof of the Relative Index Conjecture

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    We prove the relative index conjecture, which in turn implies that the set of embeddable deformations of a strictly pseudoconvex CR-structure on a compact 3-manifold is closed in the C\infty-topology.Comment: 5 page

    Harnack Inequalities and Heat-kernel Estimates for Degenerate Diffusion Operators Arising in Population Biology

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    This paper continues the analysis, started in [2, 3], of a class of degenerate elliptic operators defined on manifolds with corners, which arise in Population Biology. Using techniques pioneered by J. Moser, and extended and refined by L. Saloff-Coste, Grigoryan, and Sturm, we show that weak solutions to the parabolic problem defined by a sub-class of these operators, which consists of those that can be defined by Dirichlet forms and have non-vanishing transverse vector field, satisfy a Harnack inequality. This allows us to conclude that the solutions to these equations belong, for positive times, to the natural anisotropic Holder spaces, and also leads to upper and, in some cases, lower bounds for the heat kernels of these operators. These results imply that these operators have a compact resolvent when acting on C0C^0 or L2.L^2. The proof relies upon a scale invariant Poincare inequality that we establish for a large class of weighted Dirichlet forms, as well as estimates to handle certain mildly singular perturbation terms. The weights that we consider are neither Ahlfors regular, nor do they generally belong to the Muckenhaupt class A2.A_2.Comment: This version corrects a small gap in the argument used to estimate the contribution of vector fields and potentials with log-divergent coefficients (the old Lemma B.2
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