Skip to main content

All Questions

Tagged with
Filter by
Sorted by
Tagged with
1 vote
0 answers
65 views

Some details about relationship between central charges and second cohomology group of the Lie algebra

S. Weinberg in his book "The quantum theory of fields" talks about central charge that appear in Lie algebra of a given Lie group. To be more precise, on page 83 in the book, he computes the ...
Mahtab's user avatar
  • 287
2 votes
0 answers
115 views

The condition of maximality in branching rules of $SO$ group representations

Let the highest weight of a $SO(2n+1)$ representation be given as $(m_1,m_2,...,m_n)$ ($m_1\geq m_2 \geq .. \geq m_n \geq 0$) and the highest weight of a $SO(2n)$ representation be $(s_1,s_2,...,s_n)$ ...
user6818's user avatar
  • 1,893
4 votes
1 answer
923 views

About using the character formula for $SO(2n)$

I have known of the following equation for characters of a $SO(2n)$ representation with highest weights $(h_1,...,h_n)$ and for $(t_1,t_2,..,t_n,t_1^{-1},t_2^{-1},..,t_n^{-1})$ being the eigenvalues ...
user6818's user avatar
  • 1,893
6 votes
1 answer
403 views

Orbits for homogenous complex polynomials under unitary rotation of variables

Let's have two complex homogeneous polynomials of degree $k$: $f(z_1,\cdots,z_n)$ and $g(z_1,\cdots,z_n)$. We consider rotations of variables in the form of $\vec{z}' = U \vec{z}$, where $U\in SU(n)$. ...
Piotr Migdal's user avatar
  • 1,612
106 votes
3 answers
10k views

Has the Lie group E8 really been detected experimentally?

A few months ago there were several math talks about how the Lie group E8 had been detected in some physics experiment. I recently looked up the original paper where this was announced, "Quantum ...
Richard Borcherds's user avatar