Lemma 62.4.2. Let $R$ be a discrete valuation ring with fraction field $K$ and residue field $\kappa $. Let $X$ be a scheme locally of finite type over $R$. Let $r \geq 0$. Let $W \subset X$ be a closed subscheme flat over $R$. Assume $\dim (W_ K) \leq r$. Then $\dim (W_\kappa ) \leq r$ and
\[ sp_{X/R}([W_ K]_ r) = [W_\kappa ]_ r \]
Proof. Taking $\mathcal{F} = \mathcal{O}_ W$ this is a special case of Lemma 62.4.1. See Chow Homology, Lemma 42.10.3. $\square$
Post a comment
Your email address will not be published. Required fields are marked.
In your comment you can use Markdown and LaTeX style mathematics (enclose it like $\pi$
). A preview option is available if you wish to see how it works out (just click on the eye in the toolbar).
All contributions are licensed under the GNU Free Documentation License.
Comments (0)