Added bornological spaces.
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@@ -3,13 +3,13 @@
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\begin{definition}[Bounded]
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\label{definition:bounded}
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Let $E$ be a TVS over $K \in \RC$ and $B \subset E$, then the following are equivalent:
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Let $(E, \topo)$ be a TVS over $K \in \RC$ and $B \subset E$, then the following are equivalent:
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\begin{enumerate}
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\item For every $U \in \cn(0)$, there exists $\lambda \in K$ such that $\lambda U \supset B$.
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\item For every $\seq{x_n} \subset B$ and $\seq{\lambda_n} \subset K$ such that $\lambda_n \to 0$, $\lambda_n x_n \to 0$ as $n \to \infty$.
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\end{enumerate}
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If the above holds, then $B$ is \textbf{bounded}. The collection $B(E)$ is the set of all bounded sets of $E$.
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If the above holds, then $B$ is \textbf{bounded}. The collection $B(E) = B(E, \topo)$ is the set of all bounded sets of $E$.
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\end{definition}
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\begin{proof}
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(1) $\Rightarrow$ (2): Let $U \in \cn_E(0)$ be circled, then there exists $k \in \natp$ such that $kU \supset B$. Since $\lambda_n \to 0$ as $n \to \infty$, there exists $N \in \natp$ such that $|\lambda_n| \le 1/k$ for all $n \ge N$. In which case, $\lambda_n x_n \in \lambda_n B \subset U$ for all $n \ge N$.
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