Results 41 to 50 of about 11,355 (303)

Q_l-cohomology projective planes and singular Enriques surfaces in characteristic two [PDF]

Épijournal de Géométrie Algébrique, 2019
We classify singular Enriques surfaces in characteristic two supporting a rank nine configuration of smooth rational curves. They come in one-dimensional families defined over the prime field, paralleling the situation in other characteristics, but ...
Matthias Schütt
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On the Kodaira Dimension of the Moduli Space of K3 Surfaces II [PDF]

, 1999
We show that the Kodaira dimension of the moduli space of polarized K3 surfaces of degree 2n is nonnegative if n = 42, 43, 51, 53, 55, 57, 59, 61, 66, 67, 69, 74, 83, 85, 105, 119 or 133.
Shigeyuki Kondō, KONDO, SHIGEYUKI
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Elliptic Fibrations on K3 Surfaces [PDF]

Proceedings of the Edinburgh Mathematical Society, 2013
AbstractThis paper consists mainly of a review and applications of our old results relating to the title. We discuss how many elliptic fibrations and elliptic fibrations with infinite automorphism groups (or Mordell–Weil groups) an algebraic K3 surface over an algebraically closed field can have.
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Conway subgroup symmetric compactifications redux

Journal of High Energy Physics, 2022
We extend the investigation in [1] of special toroidal compactifications of heterotic string theory for which the half-BPS states provide representations of subgroups of the Conway group.
Zihni Kaan Baykara, Jeffrey A. Harvey
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Quasi-BPS categories for K3 surfaces

Forum of Mathematics, Pi
We introduce and begin the study of quasi-BPS categories for K3 surfaces, which are a categorical version of the BPS cohomologies for K3 surfaces.
Tudor Padurariu, Yukinobu Toda
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Hilbert series and applications to graded rings

International Journal of Mathematics and Mathematical Sciences, 2003
This paper contains a number of practical remarks on Hilbert series that we expect to be useful in various contexts. We use the fractional Riemann-Roch formula of Fletcher and Reid to write out explicit formulas for the Hilbert series P(t) in a number ...
Selma Altinok
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F-theory and heterotic duality, Weierstrass models from Wilson lines

European Physical Journal C: Particles and Fields, 2020
We present how to construct elliptically fibered K3 surfaces via Weierstrass models which can be parametrized in terms of Wilson lines in the dual heterotic string theory.
Lilian Chabrol
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Area in real K3-surfaces

EMS Surveys in Mathematical Sciences, 2021
For a real K3-surface X , one can introduce areas of connected components of the real point set \mathbb{R}X of X
Itenberg, Ilia, Mikhalkin, Grigory
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Modular curves and the refined distance conjecture

Journal of High Energy Physics, 2021
We test the refined distance conjecture in the vector multiplet moduli space of 4D N $$ \mathcal{N} $$ = 2 compactifications of the type IIA string that admit a dual heterotic description.
Daniel Kläwer
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On elliptic K3 surfaces.

Michigan Mathematical Journal, 2000
110 pages, with a table; Lemma 5.2 and minor typos are corrected, some references are updated, the table is not ...
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