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product measure (Definition)

Let $ (E_1, \mathcal{B}_1(E_1))$ and $ (E_2, \mathcal{B}_2(E_2))$ be two measurable spaces, with measures $ \mu_1$ and $ \mu_2$. Let $ \mathcal{B}_1 \times \mathcal{B}_2$ be the sigma algebra on $ E_1 \times E_2$ generated by subsets of the form $ B_1 \times B_2$, where $ B_1 \in \mathcal{B}_1(E_1)$ and $ B_2 \in \mathcal{B}_2(E_2)$.

The product measure $ \mu_1 \times \mu_2$ is defined to be the unique measure on the measurable space $ (E_1 \times E_2, \mathcal{B}_1 \times \mathcal{B}_2)$ satisfying the property

$\displaystyle \mu_1 \times \mu_2(B_1 \times B_2) = \mu_1(B_1) \mu_2(B_2)$    for all $\displaystyle B_1 \in \mathcal{B}_1(E_1),\ B_2 \in \mathcal{B}_2(E_2). $



"product measure" is owned by djao.
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infinite product measure (Definition) by CWoo
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Cross-references: property, subsets, generated by, sigma algebra, measures, measurable spaces
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This is version 3 of product measure, born on 2001-11-17, modified 2004-04-05.
Object id is 952, canonical name is ProductMeasure.
Accessed 5431 times total.

Classification:
AMS MSC28A35 (Measure and integration :: Classical measure theory :: Measures and integrals in product spaces)

Pending Errata and Addenda
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Infinite dimensional product spaces by iwnbap on 2004-06-10 02:10:13
Can these definitions be generalized to the infinite dimensional case? There's something along these lines in Halmos, but I'm not sure that this article and he are talking about the same thing.
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