【摘 要】
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Let X be a smooth and geometrically integral variety over a number field k. The descent theory of Colliot-Thelene and Sansuc describes arithmetic properties of X in terms of X-torsors under kgroups of
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Let X be a smooth and geometrically integral variety over a number field k. The descent theory of Colliot-Thelene and Sansuc describes arithmetic properties of X in terms of X-torsors under kgroups of multiplicative type. It interprets the Brauer-Manin obstruction to the existence of rational points(or to weak approximation)on X in terms of the descent obstruction defined by universal torsors. In this talk, we will give some progress on the descent theory and its applications to integral points(or to strong approximation).
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