Loading web-font TeX/Math/Italic

The Stacks project

Definition 10.149.2. Let R \to S be a formally unramified ring map.

  1. The universal first order thickening of S over R is the surjection of R-algebras S' \to S of Lemma 10.149.1.

  2. The conormal module of R \to S is the kernel I of the universal first order thickening S' \to S, seen as an S-module.

We often denote the conormal module C_{S/R} in this situation.


Comments (0)

There are also:

  • 4 comment(s) on Section 10.149: Conormal modules and universal thickenings

Your email address will not be published.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).

Unfortunately JavaScript is disabled in your browser, so the comment preview function will not work.

All contributions are licensed under the GNU Free Documentation License.