Results 1 to 10 of about 722 (106)
An atlas of K3 surfaces with finite automorphism group [PDF]
Épijournal de Géométrie Algébrique, 2022 We study the geometry of the K3 surfaces $X$ with a finite number automorphisms and Picard number $\geq 3$. We describe these surfaces classified by Nikulin and Vinberg as double covers of simpler surfaces or embedded in a projective space.
Xavier Roulleau
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Vanishing Property of BRST Cohomology for Modified Highest Weight Modules
Axioms, 2023 We construct certain modified highest weight modules which are called quasi highest weight modules in this paper. Using the quasi highest weight modules, we introduce a new category of modules over an affine Lie superalgebra which contains projective ...
Namhee Kwon
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Ramified cover of varieties with nef cotangent bundle
Comptes Rendus. Mathématique, 2022 We construct examples to show that having nef cotangent bundle is not preserved under finite ramified covers. Our examples also show that a projective manifold with Stein universal cover may not have nef cotangent bundle, disproving a conjecture of Liu ...
Wang, Yiyu
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Covers and Envelopes by Submodules or Quotient-Modules
Journal of Mathematics, 2023 Let R be a ring, X a class of left R-modules, S the class of submodules of X, and Q the class of quotient-modules of X. It is shown that SQ is precovering (preenveloping) if and only if every injective (projective) left R-module has an X-precover (X ...
Yuedi Zeng
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Journal of Mathematics, 2022 In this paper, we investigate the notions of X⊥-projective, X-injective, and X-flat modules and give some characterizations of these modules, where X is a class of left modules. We prove that the class of all X⊥-projective modules is Kaplansky.
Arunachalam Umamaheswaran +4 more
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Shimura subvarieties via endomorphisms
Comptes Rendus. Mathématique, 2022 We prove that there exist two families in $\mathcal{M}_2, \mathcal{M}_3$ of non-Galois covers of the projective line whose Jacobians trace out Shimura subvarieties of $\mathcal{A}_2, \mathcal{A}_3$. They provide the first two explicit examples of Shimura
Spelta, Irene
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Covering Rational Surfaces with Rational Parametrization Images
Mathematics, 2021 Let S be a rational projective surface given by means of a projective rational parametrization whose base locus satisfies a mild assumption. In this paper we present an algorithm that provides three rational maps f,g,h:A2⇢S⊂Pn such that the union of the ...
Jorge Caravantes +3 more
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Geometric correction for satellite image of Mosul city using 3D methods
Journal of Kufa-Physics, 2020 The important preprocessing techniques for remote sensing data and geometrical alteration is the geometric correction. In this paper ,it covers two models which are used in to three dimensions the physical model and the projective Transformation for ...
Israa Hussein, Nawal K.Ghazal
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Semihollow-Lifting Modules and Projectivity
مجلة بغداد للعلوم, 2022 Throughout this paper, T is a ring with identity and F is a unitary left module over T. This paper study the relation between semihollow-lifting modules and semiprojective covers. proposition 5 shows that If T is semihollow-lifting, then every semilocal
Anfal Hasan Dheyab +2 more
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Bright, dark, periodic and kink solitary wave solutions of evolutionary Zoomeron equation
Results in Physics, 2022 The modified auxiliary equation (MAE) approach and the generalized projective Riccati equation (GPRE) method are used for the first time to solve Zoomeron problem which provided different types of exact traveling wave solutions, including some new ...
Shao-Wen Yao +5 more
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