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Feb 26, 2011 at 11:44 vote accept Tommaso Centeleghe
Feb 25, 2011 at 1:39 answer added François Brunault timeline score: 4
Feb 24, 2011 at 19:58 answer added David E Speyer timeline score: 2
Feb 24, 2011 at 12:09 comment added François Brunault @Tommaso : my feeling is that the equality you mention seems plausible. What you're asking seems to be a generalization of the isomorphism $\mathbf{Z}[[X]]/(X-p) \cong \mathbf{Z}_p$, but I don't see the proof in general...
Feb 24, 2011 at 10:56 comment added Tommaso Centeleghe Nice, what are your feelings about the question then? Thanks.
Feb 24, 2011 at 10:14 comment added François Brunault The ideal $\ker \varphi_{\alpha,\nu}$ is indeed principal. The proof is as follows : $\mathbf{Z}[[X]]$ is a Noetherian unique factorization domain, so every prime ideal of height $1$ is principal. But $\mathbf{Z}[[X]]$ has Krull dimension $2$ and the image of $\varphi_{\alpha,\nu}$ is not a field, so $\ker \varphi_{\alpha,\nu}$ is principal.
Feb 22, 2011 at 19:43 answer added Pace Nielsen timeline score: 3
Feb 22, 2011 at 14:59 history edited Tommaso Centeleghe CC BY-SA 2.5
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Feb 22, 2011 at 14:54 history edited Tommaso Centeleghe CC BY-SA 2.5
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Feb 22, 2011 at 12:29 comment added François Brunault Maybe you could define $\varphi_{\alpha,\nu}$ on $\mathbf{Z}_p[[X]]$ instead ? Then you could try to use the Weierstrass preparation theorem. I don't know though if $\ker \varphi_{\alpha,\nu}$ is principal in your setting.
Feb 22, 2011 at 11:53 answer added Laurent Moret-Bailly timeline score: 3
Feb 22, 2011 at 9:42 history asked Tommaso Centeleghe CC BY-SA 2.5