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    An Improved Distributed Algorithm for Maximal Independent Set

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    The Maximal Independent Set (MIS) problem is one of the basics in the study of locality in distributed graph algorithms. This paper presents an extremely simple randomized algorithm providing a near-optimal local complexity for this problem, which incidentally, when combined with some recent techniques, also leads to a near-optimal global complexity. Classical algorithms of Luby [STOC'85] and Alon, Babai and Itai [JALG'86] provide the global complexity guarantee that, with high probability, all nodes terminate after O(logn)O(\log n) rounds. In contrast, our initial focus is on the local complexity, and our main contribution is to provide a very simple algorithm guaranteeing that each particular node vv terminates after O(logdeg(v)+log1/ϵ)O(\log \mathsf{deg}(v)+\log 1/\epsilon) rounds, with probability at least 1ϵ1-\epsilon. The guarantee holds even if the randomness outside 22-hops neighborhood of vv is determined adversarially. This degree-dependency is optimal, due to a lower bound of Kuhn, Moscibroda, and Wattenhofer [PODC'04]. Interestingly, this local complexity smoothly transitions to a global complexity: by adding techniques of Barenboim, Elkin, Pettie, and Schneider [FOCS'12, arXiv: 1202.1983v3], we get a randomized MIS algorithm with a high probability global complexity of O(logΔ)+2O(loglogn)O(\log \Delta) + 2^{O(\sqrt{\log \log n})}, where Δ\Delta denotes the maximum degree. This improves over the O(log2Δ)+2O(loglogn)O(\log^2 \Delta) + 2^{O(\sqrt{\log \log n})} result of Barenboim et al., and gets close to the Ω(min{logΔ,logn})\Omega(\min\{\log \Delta, \sqrt{\log n}\}) lower bound of Kuhn et al. Corollaries include improved algorithms for MIS in graphs of upper-bounded arboricity, or lower-bounded girth, for Ruling Sets, for MIS in the Local Computation Algorithms (LCA) model, and a faster distributed algorithm for the Lov\'asz Local Lemma

    Integration of the relativistic equations of motion of an artificial earth satellite

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    Perturbation method for relativistic motion analysis on earth orbiting spacecraf

    On a periodic solution of the central differential equation in the relativity theory of gravitation

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    Periodic solution of central differential equation in relativity theory of gravitatio
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