Metric on compact set with one point less












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Let $K$ be a compact metric space. Now remove one point from it. Is there a metric on $K$ with one point removed that generates the same topology as the initial metric but is such that the space $K$ with one point removed is still complete?










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    Let $K$ be a compact metric space. Now remove one point from it. Is there a metric on $K$ with one point removed that generates the same topology as the initial metric but is such that the space $K$ with one point removed is still complete?










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      Let $K$ be a compact metric space. Now remove one point from it. Is there a metric on $K$ with one point removed that generates the same topology as the initial metric but is such that the space $K$ with one point removed is still complete?










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      Let $K$ be a compact metric space. Now remove one point from it. Is there a metric on $K$ with one point removed that generates the same topology as the initial metric but is such that the space $K$ with one point removed is still complete?







      calculus real-analysis general-topology analysis metric-spaces






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      asked Nov 29 at 0:27









      Sascha

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          If $(K,d)$ is any complete metric space and $x in K$ then $D(u,v)=d(u,v)+|frac 1 {d(u,x)} -frac 1 {d(v,x)}|$ makes $Ksetminus {x}$ a complete metric space and $d$ is equivalent to $D$ on $Ksetminus {x}$.






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            This technique can be modified to work for all $G_delta$ subsets of a complete metric space.
            – Henno Brandsma
            Dec 2 at 10:11











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          1 Answer
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          1 Answer
          1






          active

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          active

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          active

          oldest

          votes









          3














          If $(K,d)$ is any complete metric space and $x in K$ then $D(u,v)=d(u,v)+|frac 1 {d(u,x)} -frac 1 {d(v,x)}|$ makes $Ksetminus {x}$ a complete metric space and $d$ is equivalent to $D$ on $Ksetminus {x}$.






          share|cite|improve this answer

















          • 1




            This technique can be modified to work for all $G_delta$ subsets of a complete metric space.
            – Henno Brandsma
            Dec 2 at 10:11
















          3














          If $(K,d)$ is any complete metric space and $x in K$ then $D(u,v)=d(u,v)+|frac 1 {d(u,x)} -frac 1 {d(v,x)}|$ makes $Ksetminus {x}$ a complete metric space and $d$ is equivalent to $D$ on $Ksetminus {x}$.






          share|cite|improve this answer

















          • 1




            This technique can be modified to work for all $G_delta$ subsets of a complete metric space.
            – Henno Brandsma
            Dec 2 at 10:11














          3












          3








          3






          If $(K,d)$ is any complete metric space and $x in K$ then $D(u,v)=d(u,v)+|frac 1 {d(u,x)} -frac 1 {d(v,x)}|$ makes $Ksetminus {x}$ a complete metric space and $d$ is equivalent to $D$ on $Ksetminus {x}$.






          share|cite|improve this answer












          If $(K,d)$ is any complete metric space and $x in K$ then $D(u,v)=d(u,v)+|frac 1 {d(u,x)} -frac 1 {d(v,x)}|$ makes $Ksetminus {x}$ a complete metric space and $d$ is equivalent to $D$ on $Ksetminus {x}$.







          share|cite|improve this answer












          share|cite|improve this answer



          share|cite|improve this answer










          answered Nov 29 at 0:36









          Kavi Rama Murthy

          48.7k31854




          48.7k31854








          • 1




            This technique can be modified to work for all $G_delta$ subsets of a complete metric space.
            – Henno Brandsma
            Dec 2 at 10:11














          • 1




            This technique can be modified to work for all $G_delta$ subsets of a complete metric space.
            – Henno Brandsma
            Dec 2 at 10:11








          1




          1




          This technique can be modified to work for all $G_delta$ subsets of a complete metric space.
          – Henno Brandsma
          Dec 2 at 10:11




          This technique can be modified to work for all $G_delta$ subsets of a complete metric space.
          – Henno Brandsma
          Dec 2 at 10:11


















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