Definition: In mathematics, a submersion is a mapping that can be embedded in a Euclidean space. More specifically, it's a function \( f : X \to Y \) where both spaces are assumed to be Hausdorff and second countable (i.e., they have the same first Baire category). A function \( f: X \to Y \) is submersive if for any open set \( U \) in \( X \), there exists a closed set
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