Per Alexandersson

Zurich, Switzerland

www2.math.su.se/~per

Age: 29

Currently interested in Schur functions, key Polynomials and semistandard Young tableaux and misc. related representation theory and combinatorics.

Phd thesis defended 2013, titled Combinatorial Methods in Complex Analysis.

I keep an eye out for interesting results related to complex dynamics, computability, and computer-assisted research. I use Mathematica extensively in my research. My other main programming languages are Java, LaTeX, PHP, C, etc.

Oh, and I like generative art.

May
2
comment chromatic polynomial of G - Join graph
@GA316: The chromatic symmetric function is what I mean, see e.g. www-math.mit.edu/~rstan/transparencies/3plus1.pdf
Apr
29
comment Do I not have the personality for a PhD?
It took me 1-2 months to understand my first path paper i read. Now I can skim through and grasp a few papers a day if I want (going from complex analysis to combinatorics also helped with this though...).
Apr
28
comment Smallest integer $k$ so that no Sudoku grid has exactly $k$ solutions
That's impressive!
Apr
28
comment How are mathematics PhDs from the USA viewed in mainland European universities?
In my experience, many American phds has few or no publications at the time of thesis defence (the papers are written after thesis completion), which I think put them at a disadvantage - also, in Europe, it is common to start a phd program after completing a masters, while in US, a phd is like a stronger alternative to a masters.
Apr
28
comment Presentation: Is using cartoon slides un-professional or fun?
I think it can be a better experience, or a worse experience, depending on how good you pull it of. I personally enjoy all types of presentations that are a bit unique - even if it is just a slide or two with a picture of the presenters dog (happens more often than you think).
Apr
28
comment Smallest integer $k$ so that no Sudoku grid has exactly $k$ solutions
Wow, that is impressive! What if you store sudokus with composite number of solutions as well? It may well be that the smallest non-constructible one is actually composite...
Apr
27
comment What restrictions apply on a purely ficticious university's online profile?
I hear that burger king is no real king either...
Apr
27
comment Self-containing trees
I interpret it as the (infinite) being self-similar in some sense - every sub-tree contains a copy isomorphic to the original tree...
Apr
27
reviewed Approve suggested edit on range of singular values of sub-matrices
Apr
27
comment chromatic polynomial of G - Join graph
You might want to look into Stanleys symmetric chromatic polynomial, which generalizes the chromatic polynomial. Perhaps you can make a stronger statement?
Apr
25
comment Unwanted Perlin Noise result
Ok, but to phrase it differently - maybe you might want to look into DS-algorithm and compare?
Apr
25
comment Unwanted Perlin Noise result
The latter image looks more like diamond-squares algorithm..
Apr
16
comment Examples of combinatorial bijections found by considering functors
@ViditNanda: My main interest is showing positivity in different polynomial bases, say Schur positivity.
Apr
16
asked Examples of combinatorial bijections found by considering functors
Apr
13
reviewed Approve suggested edit on When is a Riemannian metric equivalent to the flat metric on $\mathbb R^n$?
Apr
12
revised Open problems/questions in representation theory and around?
added an example
Apr
10
comment Tableaux with limited rows and complementary skew shapes
There must be some mistake in your formulation, $\mu_d - \mu_1$ is negative... but now I see what you mean...
Apr
9
comment Tableaux with limited rows and complementary skew shapes
There is an easy bijection if you restrict the numbers to be between $1$ and $\mu_1$ - the column $i$ in $\bar{\mu}$ contains the complement of the elements in column $d-i$ in $\mu$, or did I misinterpret the question?
Apr
8
comment Doing a math PhD with a great deal of student debt
Tutoring a few hours a week can be beneficial.
Apr
8
comment The overwhelming silence in shy classes
I like to make jokes sometimes, but not on students expense... Also, I like painting an imaginary situation that is a bit crazy (and funny). This is particularly easy to do in combinatorics..
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