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Recall that $S_5$ acts on $\mathbb C^5$ by permuting its coordinates and that $\mathbb C^5$ decomposes as $V\oplus W$ where $W$ is the trivial representation and $V$ has dimension $4$. Show that the alternating square of $V$, which has dimension $6$, is irreducible. What is the tableau which corresponds to this representation?

Of course, $V$ is the natural representation and $W$ is the trivial representation. I could show that the alternating square of $V$ is irreducible. But, I don't have any idea how to find the tableau which corresponds to this representation.

As David A Craven points out, the degrees of the characters of $S_5$ are $1,1,4,4,5,5,6$. But, how does that connect with the shape of the tableau? In general, I don't know any relation between degree of a character and tableau corresponding to that character. It would help if anyone can provide any information about it.

I know the Hook Length formula in the sense that the number of standard Young tableaux of a given shape is given by $\frac{n!}{\prod h_{ij}}$ but I really don't know how to connect that to degree of representation.

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    $\begingroup$ What do you know? The character degrees? Hook formula? Murnaghan-Nakayama? Give us some ideas. $\endgroup$ Commented Apr 28, 2023 at 19:57
  • $\begingroup$ @DavidA.Craven I know Hook Formula and I know degree of characters $\endgroup$ Commented Apr 28, 2023 at 20:09
  • $\begingroup$ So work out the degrees of $S_5$. $\endgroup$ Commented Apr 28, 2023 at 20:15
  • $\begingroup$ @DavidA.Craven by character degrees, I guess you meant the value of the character at identity, right? How will that help to determine the tableau? $\endgroup$ Commented Apr 28, 2023 at 20:18
  • $\begingroup$ Have you tried to compute the character degrees of $S_5$ using the hook formula? that is literally the first thing you should do. $\endgroup$ Commented Apr 28, 2023 at 20:19

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