On the descent conjecture for rational points and zero-cycles

Fuente: arXiv
Saved in:
Bibliographic Details
Main Author: Linh, Nguyen Manh
Format: Preprint
Published: 2023
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866908776606466048
author Linh, Nguyen Manh
author_facet Linh, Nguyen Manh
contents The descent method is one of the approaches to study the Brauer--Manin obstruction to the local--global principle and to weak approximation on varieties over number fields, by reducing the problem to ``descent varieties''. In recent lecture notes by Wittenberg, he formulated a ``descent conjecture'' for torsors under linear algebraic groups. The present article gives a proof of this conjecture in the case of connected groups, generalizing the toric case from the previous work of Harpaz--Wittenberg. As an application, we deduce directly from Sansuc's work the theorem of Borovoi for homogeneous spaces of connected linear algebraic groups with connected stabilizers. We are also able to reduce the general case to the case of finite (étale) torsors. When the set of rational points is replaced by the Chow group of zero-cycles, an analogue of the above conjecture for arbitrary linear algebraic groups is proved.
format Preprint
id arxiv_https___arxiv_org_abs_2305_13228
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle On the descent conjecture for rational points and zero-cycles
Linh, Nguyen Manh
Algebraic Geometry
Number Theory
11R34, 14G05, 14G12
The descent method is one of the approaches to study the Brauer--Manin obstruction to the local--global principle and to weak approximation on varieties over number fields, by reducing the problem to ``descent varieties''. In recent lecture notes by Wittenberg, he formulated a ``descent conjecture'' for torsors under linear algebraic groups. The present article gives a proof of this conjecture in the case of connected groups, generalizing the toric case from the previous work of Harpaz--Wittenberg. As an application, we deduce directly from Sansuc's work the theorem of Borovoi for homogeneous spaces of connected linear algebraic groups with connected stabilizers. We are also able to reduce the general case to the case of finite (étale) torsors. When the set of rational points is replaced by the Chow group of zero-cycles, an analogue of the above conjecture for arbitrary linear algebraic groups is proved.
title On the descent conjecture for rational points and zero-cycles
topic Algebraic Geometry
Number Theory
11R34, 14G05, 14G12
url https://arxiv.org/abs/2305.13228