Is the Quotient Space X/Y Hausdorff When X is Locally Compact?

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SUMMARY

The discussion centers on the question of whether the quotient space X/Y is Hausdorff when X is a locally compact Hausdorff space and Y is a subspace. Participants highlight the need to separate points in X that are not in Y using disjoint neighborhoods, emphasizing the importance of understanding locally compact spaces and the properties of Hausdorff spaces. The challenge lies in connecting the concepts of quotient spaces and subspaces, particularly in ensuring that neighborhoods remain disjoint after collapsing Y to a point. The conversation indicates a need for clarity on definitions and properties related to these topological concepts.

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christianrhiley
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Problem:
Let X be a locally compact Hausdorff space, Y a subspace. Show that the quotient space X/Y is a Hausdorff space.

My attempt at a solution:
I don't have a solution. I cannot connect a Hausdorff space with a quotient space.

Since X is compact Hausdorff x,y \in X s.t. x and y can be separated by neighborhoods if \exists a neighborhood U of x and V of y s.t. U /\ V = \phi. Now, somehow this implies that, for open sets U, the \bigcup U \subset X are disjoint.
 
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Normally, a topological space is quotiented by an equivalence relation, not a subspace.
 
if you are collapsing the subspace Y to a point, maybe you want a closed subspace?

then you would be asking whether any point not in that subspace can be separated from it by disjoint open neighborhoods.

it still seems kind of odd. i guess i need more definitions. what does locally compact mean?in a hausdorff space, distinct points have disjoint open neighborhoods, so you want them to still be disjoint after collapsing Y? so you need disjoint nbhds that also miss Y? (and that's for points not themselves contained in Y...
 
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