counterexample in topology [duplicate]
Matthew Harrington
We know path connectedness implies connectedness . Is the other direction true or false? I ve been trying to prove it but cannot do it. I cannot find a counter-example either. math is hard.
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$\begingroup$My favorite counterexample is Cantor's leaky tent.
Not only is it connected, but not path connected, removing a single point renders it completely disconnected! (Since I haven't taken topology yet, this is what prompted me to look up what "connected" really means)
$\endgroup$ 1 $\begingroup$Look up the topologist' sine. It is not true. That is why you cannot prove it :p.
Another funky one is $\mathbb{R}_{\text{cocountable}}$.
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