Box product-closed property of topological spaces

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This article defines a metaproperty of topological spaces: a property that can be evaluated to true/false for any property of topological spaces
View a complete list of metaproperties of topological spaces
View topological space properties satisfying this metaproperty| View topological space properties dissatisfying this metaproperty
VIEW RELATED: topological space metaproperty satisfactions| topological space metaproperty dissatisfactions

Definition

Suppose α is a property of topological spaces, i.e., for any topological space X, X either satisfies α or does not satisfy α. Then, we say that α is a box product-closed property of topological spaces if for any (possibly finite, possibly infinite) collection of topological spaces Xi,iI, all of which satisfy α, the product space iIXi, endowed with the box topology, also satisfies α.

Relation with other metaproperties

Weaker metaproperties

Other related metaproperties

To understand the relation between these concepts:

  • Examples of properties of topological spaces that are both product-closed and box product-closed: T1 space, Hausdorff space
  • Examples of properties that are box product-closed but not product-closed: discrete space
  • Examples of properties that are product-closed but not box product-closed: compact space, connected space. Basically this list includes properties that are about smallness or intimacy of some sort. The box topology makes separation easier.