Two representations of a group 
and 
are said to be orthogonal if
 |
for 
,
where the sum is over all elements 
of the representation.
Orthogonal Group Representations
See also
GroupExplore with Wolfram|Alpha
Cite this as:
Weisstein, Eric W. "Orthogonal Group Representations." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/OrthogonalGroupRepresentations.html