Added local L^p spaces.
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\input{./duality.tex}
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\input{./duality.tex}
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\input{./ui.tex}
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\input{./ui.tex}
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\input{./seq.tex}
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\input{./seq.tex}
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\input{./local.tex}
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src/fa/lp/local.tex
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src/fa/lp/local.tex
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\section{Locally Integrable Functions}
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\label{section:locally-integrable}
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\begin{definition}[Locally Integrable*]
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\label{definition:locally-integrable}
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Let $(X, \cm, \cf, \mu)$ be a \hyperref[scaffolded]{definition:measure-scaffold} measure space, $E$ be a normed vector space over $K \in \RC$, $f: X \to E$ be strongly measurable, and $p \in [1, \infty]$, then $f$ is \textbf{locally $p$-integrable} if for every $A \in \cf$, $\int_A \norm{f}_A^p d\mu < \infty$.
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The set $\mathcal{L}^p_\cf(X, \cm, \mu; E) = \mathcal{L}^p_\cf(X; E) = \mathcal{L}^p_\cf(\mu; E)$ is the space of all locally $p$-integrable $E$-valued functions on $X$.
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\end{definition}
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\begin{definition}[Locally Bounded*]
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\label{definition:locally-bounded-measure}
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Let $(X, \cm, \cf, \mu)$ be a \hyperref[scaffolded]{definition:measure-scaffold} measure space, $E$ be a normed vectorr space over $K \in \RC$, and $f: X \to E$ be strongly measurable, then $f$ is \textbf{essentially bounded} if for every $A \in \cf$, $\norm{\one_A f}_{L^\infty(A; E)} < \infty$.
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The set $\mathcal{L}^\infty_\cf(X, \cm, \mu; E) = \mathcal{L}^\infty_\cf(X; E) = \mathcal{L}^\infty_\cf(\mu; E)$ is the space of all locally bounded $E$-valued functions on $X$.
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\end{definition}
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\begin{definition}[Local $L^p$ Space*]
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\label{definition:local-lp-space}
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Let $(X, \cm, \cf, \mu)$ be a \hyperref[scaffolded]{definition:measure-scaffold} measure space, $E$ be a normed vector space over $K \in \RC$, and $p \in [1, \infty]$. For each $A \in \cf$ and $f \in \mathcal{L}^p_\cf(X, \cm, \mu; E)$, let $[f]_{L^p_A(X; \mu)} = \norm{\one_A f}_{L^p(X; \mu)}$, then the $[\cdot]_{L^p_A(X; \mu)}$ is a seminorm on \hyperref[$\mathcal{L}^p_\cf(X; E)$]{definition:locally-integrable}. The set
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\[
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L^p_\cf(X, \cm, \mu; E) = \mathcal{L}^p_\cf(X, \cm, \mu; E)/\bracs{f|f = 0\text{ a.e.}}
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\]
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equipped with the seminorms $\bracsn{[\cdot]_{L^p_A(X;\mu)}|A \in \cf}$ is a separated locally convex space, and the \textbf{local $L^p$ space} of $(X, \cm, \mu)$.
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\end{definition}
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\begin{lemma}
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\label{lemma:gluing-local-lp}
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Let $(X, \cm, \cf, \mu)$ be a \hyperref[scaffolded]{definition:measure-scaffold} localisable measure space, $E$ be a normed vector space over $K \in \RC$, $p \in [1, \infty]$, and $\bracsn{f_A}_{A \in \cf}$ such that:
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\begin{enumerate}[label=(\alph*)]
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\item For each $A \in \cf$, $f_A \in \mathcal{L}^p(A; E)$.
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\item For each $A, B \in \cf$, $f_A|_{A \cap B} = f_B|_{A \cap B}$ almost everywhere.
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\item $\bigcup_{A \in \cf}f_A(A)$ is a separable subset of $E$.
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\end{enumerate}
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then there exists a unique $f \in L^p_\cf(X; E)$ such that $f|_A = f_A$ for all $A \in \cf$.
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\end{lemma}
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\begin{proof}
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By the \hyperref[gluing lemma for measurable functions]{lemma:gluing-measurable}.
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\end{proof}
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