Locally Euclidean Space is Locally Path-Connected

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Theorem

Let $M$ be a locally Euclidean space of some dimension $d$.


Then $M$ is locally path-connected.


Proof

Let $m \in M$ be arbitrary.


From Locally Euclidean Space has Countable Local Basis Homeomorphic to Open Balls:

there exists a local basis $\family{U_n}_{n \in \N}$ of $m$ where each $U_n$ is the homeomorphic image of an open ball of $\R^d$.


For all $n \in \N$, let:

$U_n = \phi_n \sqbrk {B_n}$

where $B_n$ is an open ball of $\R^d$ and $\phi_n: B_n \to U_n$ is a homeomorphism.


From Open Ball is Path-Connected:

$B_n$ is path-connected.


From Continuous Image of Path-Connected Set is Path-Connected: Metric Space:

$U_n$ is path-connected.


Hence $m$ has a local basis of path-connected sets.


Since $m$ was arbitrary, it follows that $M$ is locally path-connected by definition.

$\blacksquare$