Every locally path connected space has a basis consisting of path connected sets

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Homework Help Overview

The discussion revolves around the concept of local path connectedness in topological spaces and the goal of demonstrating that every locally path connected space has a basis consisting of path connected sets that generates its topology.

Discussion Character

  • Conceptual clarification, Problem interpretation, Assumption checking

Approaches and Questions Raised

  • Participants explore the definition of local path connectedness and its implications for establishing a basis of path connected sets. There is a focus on the relationship between the class definition and a more standard definition of local path connectedness. Questions arise regarding the equivalence of these definitions and the existence of path connected neighborhoods.

Discussion Status

The discussion is ongoing, with participants raising questions about the definitions involved and the necessary steps to prove the desired result. Some guidance has been offered regarding the exploration of open neighborhoods that are path connected, but no consensus has been reached on the equivalence of definitions or the proof strategy.

Contextual Notes

Participants express uncertainty about the correctness of the definition provided in class and its potential discrepancies with more standard definitions. There is also mention of the need to clarify the definition of a basis in the context of the discussion.

Esran
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Homework Statement



The definition for local path connectedness is the following: let x be in X. Then for each open subset U of X such that x is in U, there exists an open V contained in U such that x is in V and the map induced by inclusion from the path components of V to the path components of U is trivial.

We wish to show that every locally path connected space has a basis of path connected sets which generates its topology.

Homework Equations



Not applicable.

The Attempt at a Solution



Normally, I'd be working with the more standard definition that there exists a neighborhood about each x in X containing a path connected open set, say U. Then, the desired basis would just be the collection of all such sets U for all x in X. But, I'm not sure the definition provided in class is equivalent to the more standard definition--I think there might be a mistake in it, as in I copied it down wrong. At least, I'm having extreme difficulties proving the class definition implies the more standard one.
 
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What happens if you take \mathcal{B}(x) all the open neighbourhoods around x which are path connected? Try to show that this is a basis?

What definition of basis are you using by the way?
 
The difficulty though is first proving that with the given definition of local path connectedness, x has such a neighborhood. After that, I know exactly what to do. Going from the class definition to the more standard one is my problem.
 
My definition of basis is as follows:

The base elements cover X. Let B1, B2 be base elements and let I be their intersection. Then for each x in I, there is a base element B3 containing x and contained in I.
 

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