diff --git a/src/fa/interpolation/complex.tex b/src/fa/interpolation/complex.tex index c52acdf..f908223 100644 --- a/src/fa/interpolation/complex.tex +++ b/src/fa/interpolation/complex.tex @@ -40,12 +40,12 @@ \item The mapping $C_\theta$ defined by $(E_0, E_1) \mapsto [E_0, E_1]_\theta$ is an interpolation functor of exact exponent $\theta$. \end{enumerate} - and functor $C_\theta$ is the \textbf{method of complex interpolation}. + and the functor $C_\theta$ is the \textbf{method of complex interpolation}. \end{definition} \begin{proof}[Proof, {{\cite[Theorem 4.1.2]{BerghInterpolation}}}. ] (1): Let $\seq{x_n} \subset [E_0, E_1]_\theta$ with $\sum_{n \in \natp}\norm{x_n}_{[E_0, E_1]_\theta} < \infty$, then there exists $\seq{f_n} \subset \cf(E_0, E_1)$ such that for each $n \in \natp$, $f_n(\theta) = x_n$ and $\norm{f_n}_{\cf(E_0, E_1)} \le 2\norm{x_n}_{[E_0, E_1]_\theta}$. Since $\cf(E_0, E_1)$ is complete, there exists $f \in \cf(E_0, E_1)$ such that $f = \sum_{n = 1}^\infty f_n$. Let $x = f(\theta)$, then since $\sum_{n = 1}^N f_n \to f$ in $\cf(E_0, E_1)$ as $N \to \infty$, $\sum_{n = N}^\infty x_n \to x$ in $[E_0, E_1]_\theta$ as $N \to \infty$. Therefore $[E_0, E_1]_\theta$ is a Banach space by \autoref{lemma:banach-criterion}. - For any $x \in E_0 \cap E_1$ and $\delta > 0$, let $f_\delta(z) = x_0 e^{(z - \theta)^2}$, then $f_\delta \in \cf(E_0, E_1)$ with $\norm{f_\delta}_{\cf(E_0, E_1)} \le e^\delta\norm{x}_{E_0 \cap E_1}$. Thus $x \in [E_0, E_1]_\theta$ with + For any $x \in E_0 \cap E_1$ and $\delta > 0$, let $f_\delta(z) = x_0 e^{\delta(z - \theta)^2}$, then $f_\delta \in \cf(E_0, E_1)$ with $\norm{f_\delta}_{\cf(E_0, E_1)} \le e^\delta\norm{x}_{E_0 \cap E_1}$. Thus $x \in [E_0, E_1]_\theta$ with \[ \norm{x}_{[E_0, E_1]_\theta} \le \norm{f}_{\cf(E_0, E_1)} \le e^\delta\norm{x}_{E_0 \cap E_1} \] diff --git a/src/measure/vector/ac.tex b/src/measure/vector/ac.tex index a669068..53cc99c 100644 --- a/src/measure/vector/ac.tex +++ b/src/measure/vector/ac.tex @@ -88,7 +88,7 @@ so $\nu$ is a vector measure. - Absolute continuity is equivalent to uniform continuity as a mapping $\cm_n \to E$, and uniform absolute continuity is equivalent to uniform equicontinuity as mappings $\cm \to E$. By the \hyperref[ArzelĂ -Ascoli Theorem]{theorem:arzela-ascoli}, $\nu \in UC(\cm_0; E)$, so $\nu \ll \mu$. + Absolute continuity is equivalent to uniform continuity as a mapping $\cm_0 \to E$, and uniform absolute continuity is equivalent to uniform equicontinuity as mappings $\cm_0 \to E$. By the \hyperref[ArzelĂ -Ascoli Theorem]{theorem:arzela-ascoli}, $\nu \in UC(\cm_0; E)$, so $\nu \ll \mu$. \end{proof}