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1 vote
0 answers
44 views

Normalizer of a Young subgroup in symmetric group

In $S_n$, a Young subgroup $S_{r_1}^{m_1}\times S_{r_2}^{m_2}\times ... S_{r_k}^{m_k}$ where $m_1\times r_1+...+m_k\times r_k=n$ has normalizer $N=S_{r_1}wr S_{m_1} \times ...\times S_{r_k}wr S_{m_k}$....
scsnm's user avatar
  • 1,303
3 votes
0 answers
84 views

Schur functors applied to irreducible representations of $S_n$

For a $d$-box Young diagram $\lambda$, the Schur functor is a functor $S_\lambda: \text{Vect}\rightarrow \text{Vect}$. If $\lambda = d$ then $S_\lambda V=S^d V$ the $d$-th symmetric power of $V$, ...
Ted Jh's user avatar
  • 479
1 vote
0 answers
21 views

Scalars by which symmetrizations of cyclic permutations act on Specht modules

Let $S_n$ be the symmetric group. Pick $a \in 2,\ldots,n$ and denote by $c_a \in \mathbb{C}[S_n]$ the symmetrization of the element $(12\ldots a)$ i.e. $c_a$ is the sum of cycles of type $a$. Let $\...
Asav's user avatar
  • 135
2 votes
1 answer
80 views

Weyl constructions for finite groups

Let $G$ be a finite group. Is there a complex finite dimensional irreducible representation $V$ such that all irreducible ones are submodules of $V^{\otimes n}$ for some $n \in \mathbb{N}$? If not, ...
Student's user avatar
  • 1,822
2 votes
1 answer
288 views

Why is the Young symmetrizer non-zero?

Suppose $\lambda$ is a partition of the natural number $n$ and $T$ is a standard Young Tableaux of shape $\lambda$. Let $$P_{\lambda}:=\lbrace g\in S_n:g\text{ preserves the rows of }T\rbrace$$ and $$...
Nephry's user avatar
  • 787
0 votes
1 answer
58 views

Young tableaux of partition $3+1+1$ for the conjugacy classes of $S_5$

I just computed the Young tableaux of partition $3+1+1$ for the conjugacy classes of $S_5$. It would be nice if anyone could confirm it's correctness. Thanks.
Omar Shehab's user avatar
3 votes
0 answers
364 views

Young tableaux to Specht polynomial to Irreducible representation for $(1,3,5) \in S_5$

What I am trying to do? Work out the irreducible representation of the group element $(1,3,5) \in S_5$ for the partition $2+2+1$ . Motivation: Learn how to calculate irreducible representation from ...
Omar Shehab's user avatar
2 votes
1 answer
384 views

Representation from Young tabloids

I am following the note Young Tableaux and the Representations of the Symmetric Group to work out a representation from a Young tableau for $S_n$. Here $\lambda$ is a partition of an integer $n$. In ...
Omar Shehab's user avatar
2 votes
1 answer
93 views

Confusing partitions of $S_5$ in two different sources

I am trying to understand the partitions of $S_5$ created by it's conjugacy classes but two sources have two different partitions. Source 1: Source 2: So, for example, in the first table, the ...
Omar Shehab's user avatar
3 votes
2 answers
2k views

Young diagram for $S_5$

I am trying to draw the Young diagram for $S_5$. I know the following pieces of information about $S_5$. The order of the group is $120$. The number of conjugacy classes and so partitions is $7$. ...
Omar Shehab's user avatar