591 research outputs found
Zero-cycles on varieties over p-adic fields and Brauer groups
In this paper, we study the Brauer-Manin pairing of smooth proper varieties
over local fields, and determine the -adic part of the kernel of one side.
We also compute the of a potentially rational surface which splits over a
wildly ramified extension.Comment: 31 pages. The proof of the main result in the local case has been
much simplified. The computations of 0-cycles on cubic surfaces have been
modifie
Relative cycles with moduli and regulator maps
Let X be a separated scheme of finite type over a field k and D a non-reduced
effective Cartier divisor on it. We attach to the pair (X, D) a cycle complex
with modulus, whose homotopy groups - called higher Chow groups with modulus -
generalize additive higher Chow groups of Bloch-Esnault, R\"ulling, Park and
Krishna-Levine, and that sheafified on gives a candidate definition
for a relative motivic complex of the pair, that we compute in weight 1.
When X is smooth over k and D is such that is a normal crossing
divisor, we construct a fundamental class in the cohomology of relative
differentials for a cycle satisfying the modulus condition, refining El-Zein's
explicit construction. This is used to define a natural regulator map from the
relative motivic complex of (X,D) to the relative de Rham complex. When X is
defined over , the same method leads to the construction of a
regulator map to a relative version of Deligne cohomology, generalizing Bloch's
regulator from higher Chow groups.
Finally, when X is moreover connected and proper over , we use
relative Deligne cohomology to define relative intermediate Jacobians with
modulus of the pair (X,D). For r= dim X, we show that
is the universal regular quotient of the Chow group of 0-cycles with modulus.Comment: 46 pages. Final version: Section 9 added and material rearranged. To
appear in Journal of the Inst. of Math. Jussie
Lefschetz theorem for abelian fundamental group with modulus
We prove a Lefschetz hypersurface theorem for abelian fundamental groups
allowing wild ramification along some divisor. In fact, we show that
isomorphism holds if the degree of the hypersurface is large relative to the
ramification along the divisor.Comment: 10 pages, final versio
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