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Fedor Bogomolov

Publications and source records attributed to Fedor Bogomolov.

At least 55 records · Page 3Linked to original sources

Reconstruction of higher-dimensional function fields

We prove that function fields of varieties of dimension at least two over an algebraic closure of a finite field are determined, modulo purely inseparable extensions, by the quotient by the second term in the lower central series of their pro-$\ell$ Galois groups.

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Constructing rational curves on K3 surfaces

We develop a mixed-characteristic version of the Mori-Mukai technique for producing rational curves on K3 surfaces. We reduce modulo p, produce rational curves on the resulting K3 surface over a finite field, and lift to characteristic zero. As an application, we prove that all complex K3 surfaces with Picard group generated by a class of degree two have an infinite number of rational curves.

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Milnor K_2 and field homomorphisms

We prove that the function field of an algebraic variety of dimension greater than 1 over an algebraically closed field of characteristic zero is determined by its first and second Milnor K-groups.

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Symmetric tensors and the geometry of subvarieties of $\Bbb P^N$

This paper following a geometric approach proves new, and reproves old, vanishing and nonvanishing results on the space of twisted symmetric differentials, $H^0(X,S^mΩ^1_X\otimes \Cal O_X(k))$ with $k\le m$, on subvarieties $X\subset \Bbb P^N$. The case of $k=m$ is special and the nonvanishing results are related to the space of quadrics containing $X$ and lead to interesting geometrical objects associated to $X$, as for example the variety of all tangent trisecant lines of $X$. The same techniques give results on the symmetric differentials of subvarieties of abelian varieties. The paper ends with new results and examples about the jump along smooth families of projective varieties $X_t$ of the symmetric plurigenera, $Q_m(X)= \dim H^0(X,S^mΩ^1_X)$, or of the $α$-twisted symmetric plurigenera, $Q_{α,m}(X)= \dim H^0(X,S^m(Ω^1_X\otimes αK_X))$.

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Special elliptic fibrations

We construct examples of elliptic fibrations of orbifold general type (in the sense of Campana) which have no etale covers dominating a variety of general type.

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Unramified Brauer groups of finite simple groups of Lie type $A_{\ell}$

We study the subgroup B_0(G) of H^2(G,Q/Z) consisting of all elements which have trivial restrictions to every Abelian subgroup of G. The group B_0(G) serves as the simplest nontrivial obstruction to stable rationality of algebraic varieties V/G where V is a faithful complex linear representation of the group G. We prove that B_0(G) is trivial for finite simple groups of Lie type A_{\ell}.

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Unramified correspondences

We study correspondences between algebraic curves defined over the separable closure of $\Q$ or $\F_p$.

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