Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Simultaneous Block Diagonalization of Matrices of Finite Order   It is well known that a set of non-defect matrices can be simultaneously
diagonalized if and only if the matrices commute. In the case of non-commuting
matrices, the best that can be achieved is simultaneous block diagonalization.
Here we give an efficient algorithm to explicitly compute a transfer matrix
which realizes the simultaneous block diagonalization of unitary matrices whose
decomposition in irreducible blocks (common invariant subspaces) is known from
elsewhere. Our main motivation lies in particle physics, where the resulting
transfer matrix must be known explicitly in order to unequivocally determine
the action of outer automorphisms such as parity, charge conjugation, or time
reversal on the particle spectrum.

23
The categories of this paper are: solv-int
22
The categories of this paper are: chao-dyn
25
The categories of this paper are: patt-sol
9
The categories of this paper are: nlin
26
The categories of this paper are: bayes-an
12
The categories of this paper are: nucl-th
29
The categories of this paper are: funct-an
24
The categories of this paper are: dg-ga
34
The categories of this paper are: chem-ph
27
The categories of this paper are: comp-gas
19
The categories of this paper are: eess
18
The categories of this paper are: econ
37
The categories of this paper are: supr-con
1
The categories of this paper are: cs
6
The categories of this paper are: astro-ph
36
The categories of this paper are: cmp-lg