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Revision difference : representations of locally compact groupoids
Version 6 Version 5
\begin{definition} \begin{definition}
Let $\grp_{lc}$ be a locally compact (topological) groupoid endowed with a Haar system Let $\grp_{lc}$ be a locally compact (topological) groupoid endowed with a Haar system
$\nu = \nu^u, u \in U_{\grp_{lc}}$. Then a \emph{representation) of $\grp_{lc}$ together with the $\nu = \nu^u, u \in U_{\grp_{lc}}$. Then a \emph{representation) of $\grp_{lc}$ together with the
its associated Haar system $\nu$ is defined as a \emph{triple} $(\mu, U_{\grp_{lc}} * \H, L)$, its associated Haar system $\nu$ is defined as a \emph{triple} $(\mu, U_{\grp_{lc}} * \H, L)$,
where: \\ where: \\
$\mu$ is a \emph{quasi-invariant measure} defined over $U_{\grp_{lc}}$, \\ $\mu$ is a \emph{quasi-invariant measure} defined over $U_{\grp_{lc}}$, \\
$U_{\grp_{lc}}*\H$ is an analytical, fibered Hilbert space or Hilbert bundle over $U_{\grp_{lc}}*\H$ is an analytical, fibered Hilbert space or Hilbert bundle over
$U_{\grp_{lc}}$, and \\ $U_{\grp_{lc}}$, and \\
$L: $U_{\grp_{lc}} \longrightarrow \textbf{Iso} (U_{\grp_{lc}}*\H )$ is a $L: $U_{\grp_{lc}} \longrightarrow \textbf{Iso} (U_{\grp_{lc}}*\H )$ is a
Borelian (or \emph{borelian}) groupoid morphism whose restriction on $U_{\grp_{lc}}$ Borelian (or \emph{borelian}) groupoid morphism whose restriction on $U_{\grp_{lc}}$
is the \emph{identification map}, that is, $U_{\textbf{Iso} (U_{\grp_{lc}}*\H)}}$ is is the \emph{identification map}, that is, $U_{\textbf{Iso} (U_{\grp_{lc}}*\H)}}$ is
being identified \emph{via} $L$ with $U_{\grp_{lc}}$. Thus, \\ being identified \emph{via} $L$ with $U_{\grp_{lc}}$. Thus, \\
$L(x)= [r(x), \tilde{L}(x), d(x)]$, \\ $L(x)= [r(x), \tilde{L}(x), d(x)]$, \\
where $ \tilde{L}(x): \H (d(x)) \longrightarrow \H (r(x))$ is a Hilbert space $ \H $ where $ \tilde{L}(x): \H (d(x)) \longrightarrow \H (r(x))$ is a Hilbert space $ \H $
isomorphism. isomorphism.
\end{definition} \end{definition}