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TheStudent
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Plancherel measure and dimension

I would like to understand what the Plancherel measure is on the dual of a compact group, in more explicit terms than with an implicit definition. Indeed, to the extent of my knowledge it is defined as the only positive Radon measure such that a certain inversion formula holds, namely $$\int_{\hat{G}} f(\pi)d\mu(\pi) = f(1).$$

What can be said more precisely when a representation is given explicitly? For instance, consider G the group of projective units of a quaternion algebra. For a ramified place v the group is compact so that the representation is finite dimensional. Do we have that $$\mu(\pi_v) = \dim(\pi_v)^{-1},$$

as in the finite case, or something similar? Are there references constructing from scratch the Plancherel measure and manipulating it?

TheStudent
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