Error in Book? Is it the Box Topology?

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Kreizhn
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Hey,

I'm reading through a book and have come across something that seems like an obvious error to me. The books says

If (X,T_X) and (Y,T_Y) are topological spaces, there's a standard way to define a topology on the Cartesian product X \times Y. If we let
\mathbb B = \{ O_X \times O_Y : O_X \in T_X, O_Y \in T_Y \}
then the topology generated by this basis is called the product topology on X \times Y

Now it's been a long time since I've done any topology, but isn't this the box topology rather than the product topology? I just want to make sure I'm not going crazy.
 
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I think the product topology and box topology coincide for finite products. If you are looking at the space X x Y in particular, then the product topology is generated by the set

\{ O_X \times Y :O_X \in T_X \} \cup \{X \times O_Y:O_Y \in T_Y \}

Finite intersections of these sets are open as well. In particular,

(O_X \times Y) \cap (X \times O_Y) = O_X \times O_Y

is open.
 
Thanks.

I think you're right. Planetmath says that they coincide when the index set is finite.
 
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