Prove: Quotient Map If p:X->Y & Z Locally Compact Hausdorff Space

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In summary, the conversation discusses the idea of proving that if p:X->Y is a quotient map and Z is a locally compact Hausdorff space, then the map m: p x i : X x Z -> Y x Z is also a quotient map. The conversation also touches on the use of the tube lemma and saturated neighborhoods in the proof. There is a question raised about whether the statement p x i (U x V) = p(U) x i(V) is true and what it means for p x i to be a quotient map. It is mentioned that more work may be needed to prove that p x i is a quotient map.
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ak416
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Prove: If p:X->Y is a quotient map and if Z is a locally compact Hausdorff space, then the map m: p x i : X x Z -> Y x Z is a quotient map.

Note: i is the identity map on Z i assume. There is a few lines of hints talking about using the tube lemma and saturated neighborhoods which i don't feel like writing at the moment (see Munkres p.186). The main problem i have have with this is why not say: p x i (U x V) = p(U) x i(V), so (p x i)^-1 (U x V) = p^-1(U) x i^-1(V) (is this not true?). Because if it is true then the result seems trivial since p is a quotient map and the identity does nothing to change the openness of V. What am i missing?
 
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What does it mean for p x i to be a quotient map? You can use what you've done to prove that p x i is continuous, but you would need to do more to prove that it's a quotient map.
 

FAQ: Prove: Quotient Map If p:X->Y & Z Locally Compact Hausdorff Space

What is a quotient map?

A quotient map is a continuous surjective map between topological spaces that identifies points in the domain that are equivalent under an equivalence relation and collapses them into a single point in the codomain.

What does it mean for a space to be locally compact?

A space is locally compact if every point in the space has a compact neighborhood. This means that there exists a closed and bounded subset of the space that contains the point and is contained within an open subset of the space.

What is the importance of the Hausdorff property?

The Hausdorff property, also known as the separation axiom, states that for any two distinct points in a topological space, there exist disjoint open sets that contain each point. This property ensures that points can be separated from each other and is important for many topological and analytical constructions.

What does it mean for a map to be continuous?

A map is continuous if the preimage of any open set in the codomain is an open set in the domain. This means that small changes in the input result in small changes in the output, and ensures that the map preserves the topological structure of the spaces.

How does the proof of the quotient map theorem work?

The proof of the quotient map theorem involves showing that if p:X->Y is a quotient map and Z is a locally compact Hausdorff space, then the quotient space Y/Z is also locally compact Hausdorff. This is done by constructing a compact neighborhood for each point in Y/Z and showing that it is homeomorphic to a compact neighborhood in Z. This ensures that the quotient space inherits the local compactness and Hausdorff properties from Z.

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