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31549
bio website iaz.uni-stuttgart.de/…
location Stuttgart, Germany
age 28
visits member for 2 years, 10 months
seen 12 hours ago

Post-Doc working in representation theory


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Jul
2
awarded  Curious
Jun
20
comment About the Schur's lemma
Answer to 3: groupprops.subwiki.org/wiki/…
Jun
3
comment Left-derived functors
@DylanMoreland Please consider converting your comment into an answer, so that this question gets removed from the unanswered tab. If you do so, it is helpful to post it to this chat room to make people aware of it (and attract some upvotes). For further reading upon the issue of too many unanswered questions, see here, here or here.
Jun
3
comment Computing ext over graded rings
@Anette Please consider self-answering your question, so that it gets removed from the unanswered tab. If you do so, it is helpful to post it to this chat room to make people aware of it (and attract some upvotes). For further reading upon the issue of too many unanswered questions, see here, here or here.
Jun
3
comment What are co-products for directed graphs?
@MartinBrandenburg Please consider converting your comment into an answer, so that this question gets removed from the unanswered tab. If you do so, it is helpful to post it to this chat room to make people aware of it (and attract some upvotes). For further reading upon the issue of too many unanswered questions, see here, here or here.
Jun
2
comment Positive semidefinite but non diagonalizable matrix -proof of non-negative eigenvalues
@user137589 Please consider converting your comment into an answer, so that this question gets removed from the unanswered tab. If you do so, it is helpful to post it to this chat room to make people aware of it (and attract some upvotes). For further reading upon the issue of too many unanswered questions, see here, here or here.
Jun
2
comment Indecomposable quiver representations
I would ask Solberg on a computer implementation, he should know. If you have a procedure to compute the predecessor of a module, then you just have to determine which $\tau^{-1}$-shift of which injective your module is. This you can do by performing the knitting procedure just on dimension vectors, which is much easier. I did that once for one orientation of $E_8$, I was finished by the end of the lunch break.
May
30
answered Indecomposable quiver representations
May
30
reviewed Leave Open show that $D$ is closed
May
27
comment Help with understanding certain basic representation theoretic objects and notation
@Aaron Please consider converting your comment into an answer, so that this question gets removed from the unanswered tab. If you do so, it is helpful to post it to this chat room to make people aware of it (and attract some upvotes). For further reading upon the issue of too many unanswered questions, see here, here or here.
May
27
answered Does anyone knows this definition? (class is an ivariant)
May
26
revised Find radical of a quiver representation
added mathjax
May
26
answered Find radical of a quiver representation
May
23
awarded  Revival
May
23
comment direct sum of vector spaces
Consider $V=\mathbb{R}^2$, $V_1=\mathbb{R}(1,0)$, $V_2=\mathbb{R}(0,1)$ and $V_i=\mathbb{R}(1,1)$.
May
23
reviewed Edit suggested edit on determine the kernel of this function, find a basis for the kernel and the dual space?
May
23
revised determine the kernel of this function, find a basis for the kernel and the dual space?
improved formatting
May
23
comment Prove that $A^k = 0 $ iff $A^2 = 0$
So my comment was basically in the direction of EuYu's answer. Did you study minimal polynomials, Cayley-Hamilton?
May
23
comment Prove that $A^k = 0 $ iff $A^2 = 0$
As I understand the exercise, $k$ is fixed. For example it is asked why $A^3=0$ implies $A^2=0$ for $2\times 2$-matrices.
May
23
comment Prove that $A^k = 0 $ iff $A^2 = 0$
Could you tell us something about the methods you are allowed to use.