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On Discretization of Tori of Compact Simple Lie Groups

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 نشر من قبل Jiri Hrivnak
 تاريخ النشر 2009
  مجال البحث فيزياء
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Three types of numerical data are provided for simple Lie groups of any type and rank. This data is indispensable for Fourier-like expansions of multidimensional digital data into finite series of $C-$ or $S-$functions on the fundamental domain $F$ of the underlying Lie group $G$. Firstly, we consider the number $|F_M|$ of points in $F$ from the lattice $P^{vee}_M$, which is the refinement of the dual weight lattice $P^{vee}$ of $G$ by a positive integer $M$. Secondly, we find the lowest set $Lambda_M$ of dominant weights, specifying the maximal set of $C-$ and $S-$functions that are pairwise orthogonal on the point set $F_M$. Finally, we describe an efficient algorithm for finding, on the maximal torus of $G$, the number of conjugate points to every point of $F_M$. Discrete $C-$ and $S-$transforms, together with their continuous interpolations, are presented in full generality.



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