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bio website plusepsilon.de
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visits member for 3 years, 10 months
seen Sep 9 at 8:51

Marc Palm

Postdoc in Mathematics

http://www.plusepsilon.de


Jul
19
answered Discrete-compact duality for nonabelian groups
Jul
17
comment What is the relationship amongst all the different kinds of spectra?
The spectrum of a unital commutative $C^*$ algebra $A$ is defined such that $Hom_{top}(Spec(A), \mathbb{C}) = A$, the same holds for the spectra in homotopy theory with different hom. So I always understand this as a question about representable functors. Does this make sense?
Jul
16
comment Sigma Algebra that is not a topology
@Joel: Interesting, I edited the answer.
Jul
14
accepted To what extent do we know the representations of GL(2,Zp)
Jul
14
comment generalisation of GL(3,R) polar decomposition
@Carnahan: It is sometimes called polar decomposition, since $PSL_2(\mathbb{R}) / PSO(2)$ is the upper halfplane $H$, and the above decompositions give you the elements of $H$ in polar coordinates, but you are right in general.
Jul
14
comment generalisation of GL(3,R) polar decomposition
I just wanted to comment that on both sides $SO_K(3)$ works and I presumably thought you might had a typo in the question=)
Jul
13
comment generalisation of GL(3,R) polar decomposition
@em12: Btw, are sure it holds for $GL(2)$?
Jul
13
comment generalisation of GL(3,R) polar decomposition
I mean just use $\sqrt{K} m \sqrt{K}^{-1}$ and using the result for $SO(3)$. If $K$ has negative eigenvalues, this strategy does not apply, since there is a problem with $\sqrt{K}$.
Jul
13
comment generalisation of GL(3,R) polar decomposition
@Spice, I wanted to say, if $K$ induces a scalar product on $\mathbb{R}^3$, the decomposition result is the same, since all scalar products are the same, since there exists $\sqrt{K}$. Then every matrix $m$ in $End(\mathbb{R}^3)$ can be given as $m=o d o'$ for $d$ diagonal and $o,o'\in SO_K(3)$.
Jul
13
comment generalisation of GL(3,R) polar decomposition
psoitive definite symmetric matrix and $SO_K$ on both sides, than I'd say yes.
Jul
13
comment To what extent do we know the representations of GL(2,Zp)
Yes since all irreducible complex representation of $GL(2, o)$ factor through the finite group $GL(2,o/n)$ for some ideal $n$. Then using $Ind_B^G Ind_1^B 1 = Ind_1^G 1$ gives all irreducible representations.
Jul
13
revised To what extent do we know the representations of GL(2,Zp)
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Jul
13
revised To what extent do we know the representations of GL(2,Zp)
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Jul
13
asked To what extent do we know the representations of GL(2,Zp)
Jul
12
revised Sigma Algebra that is not a topology
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Jul
12
comment Sigma Algebra that is not a topology
How to render the brackets correctly?
Jul
12
answered Sigma Algebra that is not a topology
Jul
11
revised Does random matrix theory make any prediction for the eigenvalue distributions of compact Riemann surfaces?
added 79 characters in body
Jul
11
comment Does random matrix theory make any prediction for the eigenvalue distributions of compact Riemann surfaces?
Thanks a lot for the short summary and the reference.
Jul
11
accepted Does random matrix theory make any prediction for the eigenvalue distributions of compact Riemann surfaces?