Homeomorphic characterization of the real line?












10














Let $A$ be a path-connected subset of $mathbb R^2$ such that the removal of any singleton from $A$ splits $A$ into two open connected components, each of which is path-connected.



Is $A$ necessarily homeomorphic to $mathbb{R}$?










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  • 3




    related post: mathoverflow.net/questions/76134/…
    – Josiah Park
    Jan 1 at 12:33










  • Possible duplicate of Topological Characterisation of the real line.
    – Chris Godsil
    8 hours ago
















10














Let $A$ be a path-connected subset of $mathbb R^2$ such that the removal of any singleton from $A$ splits $A$ into two open connected components, each of which is path-connected.



Is $A$ necessarily homeomorphic to $mathbb{R}$?










share|cite|improve this question




















  • 3




    related post: mathoverflow.net/questions/76134/…
    – Josiah Park
    Jan 1 at 12:33










  • Possible duplicate of Topological Characterisation of the real line.
    – Chris Godsil
    8 hours ago














10












10








10


1





Let $A$ be a path-connected subset of $mathbb R^2$ such that the removal of any singleton from $A$ splits $A$ into two open connected components, each of which is path-connected.



Is $A$ necessarily homeomorphic to $mathbb{R}$?










share|cite|improve this question















Let $A$ be a path-connected subset of $mathbb R^2$ such that the removal of any singleton from $A$ splits $A$ into two open connected components, each of which is path-connected.



Is $A$ necessarily homeomorphic to $mathbb{R}$?







gn.general-topology gt.geometric-topology






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edited Jan 1 at 12:34









YCor

27.1k380132




27.1k380132










asked Jan 1 at 12:07









James Baxter

23612




23612








  • 3




    related post: mathoverflow.net/questions/76134/…
    – Josiah Park
    Jan 1 at 12:33










  • Possible duplicate of Topological Characterisation of the real line.
    – Chris Godsil
    8 hours ago














  • 3




    related post: mathoverflow.net/questions/76134/…
    – Josiah Park
    Jan 1 at 12:33










  • Possible duplicate of Topological Characterisation of the real line.
    – Chris Godsil
    8 hours ago








3




3




related post: mathoverflow.net/questions/76134/…
– Josiah Park
Jan 1 at 12:33




related post: mathoverflow.net/questions/76134/…
– Josiah Park
Jan 1 at 12:33












Possible duplicate of Topological Characterisation of the real line.
– Chris Godsil
8 hours ago




Possible duplicate of Topological Characterisation of the real line.
– Chris Godsil
8 hours ago










1 Answer
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Ward has given the following characterization of the real line: a connected, locally connected separable metric space in which each point is a cut point, i.e., its removal splits the space into two connected subsets (Proc. London Math. Soc. 1936). This implies a positive answer to your question, assuming the set has more than one point.






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    19














    Ward has given the following characterization of the real line: a connected, locally connected separable metric space in which each point is a cut point, i.e., its removal splits the space into two connected subsets (Proc. London Math. Soc. 1936). This implies a positive answer to your question, assuming the set has more than one point.






    share|cite|improve this answer


























      19














      Ward has given the following characterization of the real line: a connected, locally connected separable metric space in which each point is a cut point, i.e., its removal splits the space into two connected subsets (Proc. London Math. Soc. 1936). This implies a positive answer to your question, assuming the set has more than one point.






      share|cite|improve this answer
























        19












        19








        19






        Ward has given the following characterization of the real line: a connected, locally connected separable metric space in which each point is a cut point, i.e., its removal splits the space into two connected subsets (Proc. London Math. Soc. 1936). This implies a positive answer to your question, assuming the set has more than one point.






        share|cite|improve this answer












        Ward has given the following characterization of the real line: a connected, locally connected separable metric space in which each point is a cut point, i.e., its removal splits the space into two connected subsets (Proc. London Math. Soc. 1936). This implies a positive answer to your question, assuming the set has more than one point.







        share|cite|improve this answer












        share|cite|improve this answer



        share|cite|improve this answer










        answered Jan 1 at 12:30









        user131781

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