All Questions
5 questions
2
votes
0
answers
45
views
Extending $G$-closed sets to permutation bases of a permutation $RG$-module
I'm curious if there are any papers or results about the following scenario:
Let $R$ be a commutative ring (I'm interested in particular in the $R = \mathbb{Z}$ case, but fields are okay too), $G$ a ...
0
votes
1
answer
187
views
Semi simplicity over commutative algebras over non-algebraically closed fields
I have already posted this on stackexchange
I have a question:
If k is an arbitrary field then is it true that if $M$ a finite dimensional $k[x, y]$ is semisimple as a $k[x]$ module and also as a $...
5
votes
3
answers
903
views
Irreducible representations and invariant subspaces
Consider two invertible n-by-n matrices, $n>2$, $X$ and $Y$ over a finite field $k$ (say for simplicity $k=\mathbb Z/ \mathbb Z_2$). Is there any reasonable way to check that there is no proper ...
5
votes
0
answers
856
views
Dual of representation is irreducible implies the representation is irreducible?
Suppose $V$ is an infinite dimensional $\mathbb{Q}_p$-representation of Lie algebra $\mathfrak{g}$ over $\mathbb{Q}_p$. If its dual representation $V^{\prime}$ is irreducible then, is it always true ...
7
votes
1
answer
455
views
Hopfian modules
My question is slightly motivated by basic results in linear algebra, for example, that if $F$ is a field then a surjective linear map $F^n \rightarrow F^n$ is injective. More generally, any ...