论文标题
在盘子集团的平坦回调上
On flat pullbacks for Chow groups
论文作者
论文摘要
这是代数方案的Chow群体的基本特性，它们在方案之间的平坦态度方面是矛盾的。尽管回调同态在代数周期的水平上很容易定义，但至关重要的步骤是表明，循环的回调可以保留有理等价，因此它降为Chow群体。本说明的目的是给出自然的捆绑理论证明，即在循环的平坦回溯下保存理性等价。
It is a fundamental property of the Chow groups of algebraic schemes that they are contra-functorial with respect to flat morphisms between schemes. While the pullback homomorphism is easy to define at the level of algebraic cycles, the crucial step is to show that the pullback of cycles preserves rational equivalence, so that it descends to the Chow groups. The purpose of this note is to give a natural sheaf theoretic proof of the preservation of rational equivalence under flat pullback on cycles.
