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Timeline for Action of a profinite group

Current License: CC BY-SA 3.0

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S May 1, 2014 at 11:28 history bounty ended Pablo
S May 1, 2014 at 11:28 history notice removed Pablo
May 1, 2014 at 11:27 vote accept Pablo
May 1, 2014 at 10:05 answer added Jeremy Rickard timeline score: 3
Apr 30, 2014 at 15:32 vote accept Pablo
May 1, 2014 at 11:27
Apr 30, 2014 at 15:32 answer added Pablo timeline score: 0
S Apr 24, 2014 at 17:05 history bounty started Pablo
S Apr 24, 2014 at 17:05 history notice added Pablo Improve details
Apr 22, 2014 at 21:16 answer added Julian Rosen timeline score: 4
Apr 22, 2014 at 21:13 comment added YCor @Alex: I assume that $I$ is supposed infinite, otherwise you're right.
Apr 22, 2014 at 20:38 comment added Pablo I think that if $G$ is finite, you may pick some nontrivial $v \in V$ and take $U = <gv : g \in G>$. This shows that the answer to 1 is yes.
Apr 22, 2014 at 20:24 comment added Alex B. I suspect that I don't understand the question, but if you take $G$ finite of order not divisible by $p$, $M$ any non-trivial irreducible $\mathbb{Q}_p[G]$-module, and $V$ a $\mathbb{Z}_p[G]$-lattice in $M$, then isn't the answer to all your questions trivially (no pun intended) "no"?
Apr 22, 2014 at 19:02 history edited Pablo CC BY-SA 3.0
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Apr 22, 2014 at 17:24 history edited Pablo CC BY-SA 3.0
added 60 characters in body
Apr 22, 2014 at 17:21 comment added Pablo Yes, I mean that the submodule will be nonntrivial, and generated as a group (forgetting the action of $G$) by finitely many elements.
Apr 22, 2014 at 17:15 comment added YCor Ah OK you just mean $\mathbb{Z}_p^I$... Question 1 looks weird: $\{0\}$ answers positively the question. Also the closed submodule generated by any element is t.f.g. as a submodule... What do you mean? A nonzero submodule that is t.f.g. as topological group?
Apr 22, 2014 at 17:12 comment added Pablo $p$ is a fixed prime not to be changed. $\mathbb{F}_p$ is a field with $p$ elements. The infinite product means that we take a power of disjoint copies of the same group, to say, vectors with coordinates in $\mathbb{Z}_p$ (only one group - not changing the prime). $G$ is assumed to be a finitely generated profinite group so compactness is not an issue.
Apr 22, 2014 at 17:05 comment added YCor Does $\mathbb{Z}_p$ denotes the $p$-adics? Do you mean $p\in I$ instead of $i\in I$ (otherwise the product is meaningless). What is $\mathbb{F}_p$? Also "i.e. $V$ is a profinite $G$-module" is not just a restatement: there is something (not hard) to check, which fails when $G$ is not assumed compact.
Apr 22, 2014 at 16:42 history asked Pablo CC BY-SA 3.0