ar X iv : a lg - g eo m / 9 20 20 27 v 2 7 A pr 1 99 2 COHOMOLOGICAL AND CYCLE - THEORETIC CONNECTIVITY
نویسنده
چکیده
One of the themes in algebraic geometry is the study of the relation between the “topology” of a smooth projective variety and a (“general”) hyperplane section. Recent results of Nori produce cohomological evidence for a conjecture that a general hypersurface of sufficently large degree should have no “interesting” cycles. We compute precise bounds for these results and show by example that there are indeed interesting cycles for degrees that are not high enough. In a different direction Esnault, Nori and Srinivas have shown connectivity for intersections of small multidegree. We show analogous cycle-theoretic connectivity results.
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