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-rw-r--r--vorlesungen/slides/2/hilbertraum/plancherel.tex23
1 files changed, 22 insertions, 1 deletions
diff --git a/vorlesungen/slides/2/hilbertraum/plancherel.tex b/vorlesungen/slides/2/hilbertraum/plancherel.tex
index 3caa54d..eaf8aaa 100644
--- a/vorlesungen/slides/2/hilbertraum/plancherel.tex
+++ b/vorlesungen/slides/2/hilbertraum/plancherel.tex
@@ -17,9 +17,12 @@ $\mathcal{B}=\{b_k\;|\; k>0\}$, $x\in H$
\end{block}
\begin{block}{Analyse: Fourier-Koeffizienten}
\begin{align*}
-a_k &= \hat{x}_k=\langle b_k, x\rangle
+a_k = \hat{x}_k &=\langle b_k, x\rangle
+\\
+\hat{x}&=\mathcal{F}x
\end{align*}
\end{block}
+\vspace{-10pt}
\begin{block}{Synthese: Fourier-Reihe}
\begin{align*}
\tilde{x}
@@ -29,6 +32,7 @@ a_k &= \hat{x}_k=\langle b_k, x\rangle
\sum_k \langle x,b_k\rangle b_k
\end{align*}
\end{block}
+\vspace{-6pt}
\begin{block}{Analyse von $\tilde{x}$}
\begin{align*}
\langle b_l,\tilde{x}\rangle
@@ -67,7 +71,24 @@ b_l,\sum_{k}\langle b_k,x\rangle b_k
\|\tilde{x}\|^2
&=
\sum_k |\hat{x}_k|^2
+=
+\|\hat{x}\|_{l^2}^2
+=
+\|\mathcal{F}x\|_{l^2}^2
+\end{align*}
+\end{block}
+\vspace{-12pt}
+\begin{block}{Isometrie}
+\begin{align*}
+\mathcal{F}
+\colon
+H \to l^2
+\colon
+x\mapsto \hat{x}
\end{align*}
+Alle separablen Hilberträume sind isometrisch zu $l^2$ via
+%Fourier-Transformation
+$\mathcal{F}$
\end{block}
\end{column}
\end{columns}