Volume 3 (2020)
Starr, Jason; Xu, Chenyang
Rational points of rationally simply connected varieties over global function fields
Annales Henri Lebesgue, Volume 3 (2020), pp. 1399-1417.

Metadata

DOI10.5802/ahl.65
Keywords rationally simply connected varieties, rational points, degenerations

Abstract

For a complex projective manifold that is rationally connected, resp. rationally simply connected, every finite subset is connected by a rational curve, resp. the spaces parameterizing these connecting rational curves are themselves rationally connected. We prove that a projective scheme over a global function field has a rational point if it deforms to a rationally simply connected variety in characteristic 0 with vanishing elementary obstruction. This gives new, uniform proofs over these fields of the Period-Index Theorem, the quasi-split case of Serre’s “Conjecture II”, and Lang’s C 2 property.


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