Interior of a contractible set












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Let $O, F subset mathbb R^n$ for $n ge 2$. Suppose $O$ is open, $F$ is closed and $O subset F$ with closure $bar{O} = F$. If we further assume that both $O$ and $F$ are contractible to the same fixed point $p in O$. Can we conclude that $F^{circ} = O$?










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    $begingroup$


    Let $O, F subset mathbb R^n$ for $n ge 2$. Suppose $O$ is open, $F$ is closed and $O subset F$ with closure $bar{O} = F$. If we further assume that both $O$ and $F$ are contractible to the same fixed point $p in O$. Can we conclude that $F^{circ} = O$?










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      $begingroup$


      Let $O, F subset mathbb R^n$ for $n ge 2$. Suppose $O$ is open, $F$ is closed and $O subset F$ with closure $bar{O} = F$. If we further assume that both $O$ and $F$ are contractible to the same fixed point $p in O$. Can we conclude that $F^{circ} = O$?










      share|cite|improve this question









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      Let $O, F subset mathbb R^n$ for $n ge 2$. Suppose $O$ is open, $F$ is closed and $O subset F$ with closure $bar{O} = F$. If we further assume that both $O$ and $F$ are contractible to the same fixed point $p in O$. Can we conclude that $F^{circ} = O$?







      general-topology






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      asked Dec 4 '18 at 8:16









      user1101010user1101010

      7751730




      7751730






















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          No. Let $F = D^n = { x in mathbb{R}^n mid lVert x rVert le 1 }$ and $O = mathring{F} setminus [1/2,1) times { (0,dots,0) }$. Both are contractible to $0$.






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            No. Let $F = D^n = { x in mathbb{R}^n mid lVert x rVert le 1 }$ and $O = mathring{F} setminus [1/2,1) times { (0,dots,0) }$. Both are contractible to $0$.






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              $begingroup$

              No. Let $F = D^n = { x in mathbb{R}^n mid lVert x rVert le 1 }$ and $O = mathring{F} setminus [1/2,1) times { (0,dots,0) }$. Both are contractible to $0$.






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                $begingroup$

                No. Let $F = D^n = { x in mathbb{R}^n mid lVert x rVert le 1 }$ and $O = mathring{F} setminus [1/2,1) times { (0,dots,0) }$. Both are contractible to $0$.






                share|cite|improve this answer









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                No. Let $F = D^n = { x in mathbb{R}^n mid lVert x rVert le 1 }$ and $O = mathring{F} setminus [1/2,1) times { (0,dots,0) }$. Both are contractible to $0$.







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                answered Dec 4 '18 at 14:59









                Paul FrostPaul Frost

                10k3932




                10k3932






























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