Results 1 to 10 of about 49 (45)
Autour de la conjecture de Tate enti\`ere pour certains produits de dimension $3$ sur un corps fini [PDF]
Épijournal de Géométrie Algébrique, 2022 Let $X$ be the product of a surface satisfying $b_2=\rho$ and of a curve over a finite field. We study a strong form of the integral Tate conjecture for $1$-cycles on $X$.
Federico Scavia
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Group-theoretic Johnson classes and a non-hyperelliptic curve with torsion Ceresa class [PDF]
Épijournal de Géométrie Algébrique, 2023 Let l be a prime and G a pro-l group with torsion-free abelianization. We produce group-theoretic analogues of the Johnson/Morita cocycle for G -- in the case of surface groups, these cocycles appear to refine existing constructions when l=2.
Dean Bisogno +3 more
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Maximal indexes of flag varieties for spin groups
Forum of Mathematics, Sigma, 2021 We establish the sharp upper bounds on the indexes for most of the twisted flag varieties under the spin groups ${\operatorname {\mathrm {Spin}}(n)}$.
Rostislav A. Devyatov +2 more
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On Bloch’s map for torsion cycles over non-closed fields
Forum of Mathematics, Sigma, 2023 We generalize Bloch’s map on torsion cycles from algebraically closed fields to arbitrary fields. While Bloch’s map over algebraically closed fields is injective for zero-cycles and for cycles of codimension at most two, we show that the generalization ...
Theodosis Alexandrou, Stefan Schreieder
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Noninjectivity of the cycle class map in continuous $\ell $ -adic cohomology
Forum of Mathematics, Sigma, 2023 Jannsen asked whether the rational cycle class map in continuous $\ell $ -adic cohomology is injective, in every codimension for all smooth projective varieties over a field of finite type over the prime field. As recently pointed out by Schreieder,
Federico Scavia, Fumiaki Suzuki
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Zero cycles on the moduli space of curves [PDF]
Épijournal de Géométrie Algébrique, 2020 While the Chow groups of 0-dimensional cycles on the moduli spaces of Deligne-Mumford stable pointed curves can be very complicated, the span of the 0-dimensional tautological cycles is always of rank 1.
Rahul Pandharipande, Johannes Schmitt
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Real rectifiable currents, holomorphic chains and algebraic cycles
Complex Manifolds, 2021 We study some fundamental properties of real rectifiable currents and give a generalization of King’s theorem to characterize currents defined by positive real holomorphic chains.
Teh Jyh-Haur, Yang Chin-Jui
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Framed transfers and motivic fundamental classes
Journal of Topology, Volume 13, Issue 2, Page 460-500, June 2020., 2020 Abstract We relate the recognition principle for infinite P1‐loop spaces to the theory of motivic fundamental classes of Déglise, Jin and Khan. We first compare two kinds of transfers that are naturally defined on cohomology theories represented by motivic spectra: the framed transfers given by the recognition principle, which arise from Voevodsky's ...
Elden Elmanto +4 more
wiley +1 more source
Complex Manifolds, 2020 We show that a 2k-current T on a complex manifold is a real holomorphic k-chain if and only if T is locally real rectifiable, d-closed and has ℋ2k-locally finite support. This result is applied to study homology classes represented by algebraic cycles.
Teh Jyh-Haur, Yang Chin-Jui
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Lefschetz (1,1)-theorem in tropical geometry [PDF]
Épijournal de Géométrie Algébrique, 2018 For a tropical manifold of dimension n we show that the tropical homology classes of degree (n-1, n-1) which arise as fundamental classes of tropical cycles are precisely those in the kernel of the eigenwave map.
Philipp Jell, Johannes Rau, Kristin Shaw
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