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Young Diagrams and Classical Groups [pdf]

math.ucr.edu

1–8 of 8 posts

Re: Young Diagrams and Classical Groups [pdf]

#2
The underlying idea is the idea of fixed points (aka spectra, diagonalizations, embedding, invariants, braids). By fixed point I mean something like the "Lawvere's fixed point theorem". https://ncatlab.org/nlab/show/Lawvere%27s+fixed+point+theore...

I have a linkdump on this

https://github.com/adamnemecek/adjoint

I also have a discord https://discord.gg/mr9TAhpyBW

Re: Young Diagrams and Classical Groups [pdf]

#4

The underlying idea is the idea of fixed points (aka spectra, diagonalizations, embedding, invariants, braids). By fixed point I mean something like the "Lawvere's fixed point theorem". https://ncatlab.org/nlab/show/Lawvere%27s+fixed+point+theore... I have a linkdump on this https://github.com/adamnemecek/adjoint I also have a discord https://discord.gg/mr9TAhpyBW

What's the discord for?

Re: Young Diagrams and Classical Groups [pdf]

#5
post #4

The underlying idea is the idea of fixed points (aka spectra, diagonalizations, embedding, invariants, braids). By fixed point I mean something like the "Lawvere's fixed point theorem". https://ncatlab.org/nlab/show/Lawvere%27s+fixed+point+theore... I have a linkdump on this https://github.com/adamnemecek/adjoint I also have a discord https://discord.gg/mr9TAhpyBW

What's the discord for?

Further discussion.

Re: Young Diagrams and Classical Groups [pdf]

#6

The underlying idea is the idea of fixed points (aka spectra, diagonalizations, embedding, invariants, braids). By fixed point I mean something like the "Lawvere's fixed point theorem". https://ncatlab.org/nlab/show/Lawvere%27s+fixed+point+theore... I have a linkdump on this https://github.com/adamnemecek/adjoint I also have a discord https://discord.gg/mr9TAhpyBW

The only two 1-dimensional representations of the symmetric group (i.e., what you can call fixed points if you squint a bit) are the ones that correspond to the partitions (n) and (1,1,...,1), which are the least interesting ones. Everything else is significantly more complicated. It's a block-diagonalization (Young seminormal form) with lots of nontrivial blocks. So no, you won't understand it in terms of fixed points (and certainly not of Lawvere's theorem, which I've never seen used in the entire subject).