Homotopy type of $mathbb{R}^3 setminus { mathrm{wedge hspace{3pt} sum hspace{3pt} of hspace{3pt} 2...












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Is there something "nice" that the space $mathbb{R}^3 setminus { mathrm{wedge hspace{3pt} sum hspace{3pt} of hspace{3pt} 2 hspace{3pt} circles} }$ is homotopy equivalent to? I know that $mathbb{R}^3 setminus {mathrm{circle}} simeq S^{2} vee S^{1}$, and that $mathbb{R}^3 setminus { mathrm{2 hspace{3pt} linked hspace{3pt} circles}} simeq S^{2} vee T^{2}$. However, I can't seem to apply either of the "visual methods" used to prove these homotopy equivalences to my case.



My wild guess is that it might be homotopic to $M_{2}$, the orientable closed surface of genus $2$, but I'm not sure if this is true at all.










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  • $begingroup$
    Hmm, I'd imagine that the proof of $mathbb R^3setminus S^1simeq S^2wedge S^1$ would generalize ...
    $endgroup$
    – Henning Makholm
    Dec 27 '18 at 21:42












  • $begingroup$
    Get a big sphere around them and draw $2$ diameters?
    $endgroup$
    – Matija Sreckovic
    Dec 27 '18 at 21:45










  • $begingroup$
    Obviously not diamaters, but... I'll check it out.
    $endgroup$
    – Matija Sreckovic
    Dec 27 '18 at 21:46






  • 3




    $begingroup$
    In general, if you remove a wedge of $n$ circles from $mathbb{R}^3$, then what is remaining is homotopy equivalent to a wedge of $S^2$ and $n$ circles.
    $endgroup$
    – Alvin Jin
    Dec 27 '18 at 22:01








  • 1




    $begingroup$
    Depends wildly on the way the circles are embedded.
    $endgroup$
    – user98602
    Dec 27 '18 at 23:18
















1












$begingroup$


Is there something "nice" that the space $mathbb{R}^3 setminus { mathrm{wedge hspace{3pt} sum hspace{3pt} of hspace{3pt} 2 hspace{3pt} circles} }$ is homotopy equivalent to? I know that $mathbb{R}^3 setminus {mathrm{circle}} simeq S^{2} vee S^{1}$, and that $mathbb{R}^3 setminus { mathrm{2 hspace{3pt} linked hspace{3pt} circles}} simeq S^{2} vee T^{2}$. However, I can't seem to apply either of the "visual methods" used to prove these homotopy equivalences to my case.



My wild guess is that it might be homotopic to $M_{2}$, the orientable closed surface of genus $2$, but I'm not sure if this is true at all.










share|cite|improve this question









$endgroup$












  • $begingroup$
    Hmm, I'd imagine that the proof of $mathbb R^3setminus S^1simeq S^2wedge S^1$ would generalize ...
    $endgroup$
    – Henning Makholm
    Dec 27 '18 at 21:42












  • $begingroup$
    Get a big sphere around them and draw $2$ diameters?
    $endgroup$
    – Matija Sreckovic
    Dec 27 '18 at 21:45










  • $begingroup$
    Obviously not diamaters, but... I'll check it out.
    $endgroup$
    – Matija Sreckovic
    Dec 27 '18 at 21:46






  • 3




    $begingroup$
    In general, if you remove a wedge of $n$ circles from $mathbb{R}^3$, then what is remaining is homotopy equivalent to a wedge of $S^2$ and $n$ circles.
    $endgroup$
    – Alvin Jin
    Dec 27 '18 at 22:01








  • 1




    $begingroup$
    Depends wildly on the way the circles are embedded.
    $endgroup$
    – user98602
    Dec 27 '18 at 23:18














1












1








1





$begingroup$


Is there something "nice" that the space $mathbb{R}^3 setminus { mathrm{wedge hspace{3pt} sum hspace{3pt} of hspace{3pt} 2 hspace{3pt} circles} }$ is homotopy equivalent to? I know that $mathbb{R}^3 setminus {mathrm{circle}} simeq S^{2} vee S^{1}$, and that $mathbb{R}^3 setminus { mathrm{2 hspace{3pt} linked hspace{3pt} circles}} simeq S^{2} vee T^{2}$. However, I can't seem to apply either of the "visual methods" used to prove these homotopy equivalences to my case.



My wild guess is that it might be homotopic to $M_{2}$, the orientable closed surface of genus $2$, but I'm not sure if this is true at all.










share|cite|improve this question









$endgroup$




Is there something "nice" that the space $mathbb{R}^3 setminus { mathrm{wedge hspace{3pt} sum hspace{3pt} of hspace{3pt} 2 hspace{3pt} circles} }$ is homotopy equivalent to? I know that $mathbb{R}^3 setminus {mathrm{circle}} simeq S^{2} vee S^{1}$, and that $mathbb{R}^3 setminus { mathrm{2 hspace{3pt} linked hspace{3pt} circles}} simeq S^{2} vee T^{2}$. However, I can't seem to apply either of the "visual methods" used to prove these homotopy equivalences to my case.



My wild guess is that it might be homotopic to $M_{2}$, the orientable closed surface of genus $2$, but I'm not sure if this is true at all.







algebraic-topology homotopy-theory






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share|cite|improve this question




share|cite|improve this question










asked Dec 27 '18 at 21:32









Matija SreckovicMatija Sreckovic

928517




928517












  • $begingroup$
    Hmm, I'd imagine that the proof of $mathbb R^3setminus S^1simeq S^2wedge S^1$ would generalize ...
    $endgroup$
    – Henning Makholm
    Dec 27 '18 at 21:42












  • $begingroup$
    Get a big sphere around them and draw $2$ diameters?
    $endgroup$
    – Matija Sreckovic
    Dec 27 '18 at 21:45










  • $begingroup$
    Obviously not diamaters, but... I'll check it out.
    $endgroup$
    – Matija Sreckovic
    Dec 27 '18 at 21:46






  • 3




    $begingroup$
    In general, if you remove a wedge of $n$ circles from $mathbb{R}^3$, then what is remaining is homotopy equivalent to a wedge of $S^2$ and $n$ circles.
    $endgroup$
    – Alvin Jin
    Dec 27 '18 at 22:01








  • 1




    $begingroup$
    Depends wildly on the way the circles are embedded.
    $endgroup$
    – user98602
    Dec 27 '18 at 23:18


















  • $begingroup$
    Hmm, I'd imagine that the proof of $mathbb R^3setminus S^1simeq S^2wedge S^1$ would generalize ...
    $endgroup$
    – Henning Makholm
    Dec 27 '18 at 21:42












  • $begingroup$
    Get a big sphere around them and draw $2$ diameters?
    $endgroup$
    – Matija Sreckovic
    Dec 27 '18 at 21:45










  • $begingroup$
    Obviously not diamaters, but... I'll check it out.
    $endgroup$
    – Matija Sreckovic
    Dec 27 '18 at 21:46






  • 3




    $begingroup$
    In general, if you remove a wedge of $n$ circles from $mathbb{R}^3$, then what is remaining is homotopy equivalent to a wedge of $S^2$ and $n$ circles.
    $endgroup$
    – Alvin Jin
    Dec 27 '18 at 22:01








  • 1




    $begingroup$
    Depends wildly on the way the circles are embedded.
    $endgroup$
    – user98602
    Dec 27 '18 at 23:18
















$begingroup$
Hmm, I'd imagine that the proof of $mathbb R^3setminus S^1simeq S^2wedge S^1$ would generalize ...
$endgroup$
– Henning Makholm
Dec 27 '18 at 21:42






$begingroup$
Hmm, I'd imagine that the proof of $mathbb R^3setminus S^1simeq S^2wedge S^1$ would generalize ...
$endgroup$
– Henning Makholm
Dec 27 '18 at 21:42














$begingroup$
Get a big sphere around them and draw $2$ diameters?
$endgroup$
– Matija Sreckovic
Dec 27 '18 at 21:45




$begingroup$
Get a big sphere around them and draw $2$ diameters?
$endgroup$
– Matija Sreckovic
Dec 27 '18 at 21:45












$begingroup$
Obviously not diamaters, but... I'll check it out.
$endgroup$
– Matija Sreckovic
Dec 27 '18 at 21:46




$begingroup$
Obviously not diamaters, but... I'll check it out.
$endgroup$
– Matija Sreckovic
Dec 27 '18 at 21:46




3




3




$begingroup$
In general, if you remove a wedge of $n$ circles from $mathbb{R}^3$, then what is remaining is homotopy equivalent to a wedge of $S^2$ and $n$ circles.
$endgroup$
– Alvin Jin
Dec 27 '18 at 22:01






$begingroup$
In general, if you remove a wedge of $n$ circles from $mathbb{R}^3$, then what is remaining is homotopy equivalent to a wedge of $S^2$ and $n$ circles.
$endgroup$
– Alvin Jin
Dec 27 '18 at 22:01






1




1




$begingroup$
Depends wildly on the way the circles are embedded.
$endgroup$
– user98602
Dec 27 '18 at 23:18




$begingroup$
Depends wildly on the way the circles are embedded.
$endgroup$
– user98602
Dec 27 '18 at 23:18










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