514,962 research outputs found

    Fourfolds

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    We have found a "non-purely-constructive" method of acquiring algebraic cycles involving multiple steps. This note tries to present the main idea in the last step by concentrating on an example of 4-folds. The method demonstrates a contrast to traditional constructions

    Leveled sub-cohomology

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    In this paper we define a functor-- leveled sub-cohomology. (It bears no relation with the level of elliptic curves). It is based on leveled cycles on a smooth projective variety, and will be expected to reveal a structure in the level

    Threefolds

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    This is an example on the cohomology of threefolds

    Rational curves on complete intersection Calabi-Yau 3-folds

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    We prove the following results. If X3X_3 is a generic complete intersection Calabi-Yau 3-fold, (1) then for each natural number dd there exists a rational map \par\hspace{1 cc} c∈Hombir(P1,X3)c\in Hom_{bir}(\mathbf P^1, X_3) of deg(c(P1))=ddeg(c(\mathbf P^1))=d, (2) further more all such cc are immersions satisfying \begin{equation} N_{c(\mathbf P^1)/ X_3}\simeq \mathcal O_{\mathbf P^1}(-1)\oplus \mathcal O_{\mathbf P^1}(-1)

    A remark on the local density approximation with the gradient corrections and the Xα_\alpha method

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    We report that the solids with narrow valence bands cannot be described by the local density approximation with the gradient corrections in the density functional theory as well as the Xα_\alpha method. In particular, in the case of completely filled valence bands, the work function is significantly underestimated by these methods for such types of solids. Also, we figured out that these deficiencies cannot be cured by the self-interaction-corrected-local-density-approximation method.Comment: 6 pages, 0 figure

    Cone construction II

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    This is the second part of two parts, titled " cone construction". In this part we prove the Lefschetz cohomologicity of the cone operator ConCon.Comment: It is combined with the revision of cone construction

    Equivalence of Coniveaus

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    On a smooth projective variety over the complex numbers, there is the coniveau from the coniveau filtration, which is called geometric coniveau. On the same variety, there is another coniveau from the maximal sub-Hodge structure, which is called Hodge coniveau. In this paper we show they are equivalent

    The cone construction via intersection theory

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    We show a method in constructing algebraic cycles via intersection theory. It leads to a proof of the Lefschetz standard conjecture.Comment: arXiv admin note: text overlap with arXiv:1801.0532

    Real intersection theory (I)

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    We introduce the notion of Lebesgue currents. They are a special type of currents involving Lebesgue measure. We apply it to define the intersection of singular cycles, which provides the foundation to the real intersection theory.Comment: arXiv admin note: text overlap with arXiv:1801.0136

    Quantum key distribution with asymmetric channel noise

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    We show that one may take advantages in both robusty and key rate of asymmetric channel noise.Comment: 2 figure
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