Skip to main content
Notice removed Draw attention by CommunityBot
Bounty Ended with no winning answer by CommunityBot
Notice added Draw attention by Ali Taghavi
Bounty Started worth 50 reputation by Ali Taghavi
added 4 characters in body
Source Link
Ali Taghavi
  • 356
  • 8
  • 31
  • 123

Is there a Riemannian structure on $\mathbb{R}^n $with two non homeomorphic compact hypersurfaces $M,N$ such that both satisfy the isoperimetric inequality. I precisely meanthe following:

$$\ell(M)=\ell(N)=\ell, A(M^o)=A(N^o)=A$$$$\ell(M)=\ell(N)=\ell,\;\; A(M^o)=A(N^o)=A$$

and for every compact hypersurface $P$ with $\ell(P)=\ell$ we have $A(P^o)\leq A$

Here $\ell(M)=\int_M vol_M$ the natural volum form on $M$ naturally arises from the volum form on the underling manifold. $A(M^o)$ is the area of the bounded component of $M^c$ wrt the volum form arising from the metric

Is there a Riemannian structure on $\mathbb{R}^n $with two non homeomorphic compact hypersurfaces $M,N$ such that both satisfy the isoperimetric inequality. I precisely meanthe following:

$$\ell(M)=\ell(N)=\ell, A(M^o)=A(N^o)=A$$

and for every compact hypersurface $P$ with $\ell(P)=\ell$ we have $A(P^o)\leq A$

Here $\ell(M)=\int_M vol_M$ the natural volum form on $M$ naturally arises from the volum form on the underling manifold. $A(M^o)$ is the area of the bounded component of $M^c$ wrt the volum form arising from the metric

Is there a Riemannian structure on $\mathbb{R}^n $with two non homeomorphic compact hypersurfaces $M,N$ such that both satisfy the isoperimetric inequality. I precisely meanthe following:

$$\ell(M)=\ell(N)=\ell,\;\; A(M^o)=A(N^o)=A$$

and for every compact hypersurface $P$ with $\ell(P)=\ell$ we have $A(P^o)\leq A$

Here $\ell(M)=\int_M vol_M$ the natural volum form on $M$ naturally arises from the volum form on the underling manifold. $A(M^o)$ is the area of the bounded component of $M^c$ wrt the volum form arising from the metric

Source Link
Ali Taghavi
  • 356
  • 8
  • 31
  • 123

Is isoperimetric hypersurface unique up to homeomorphism?

Is there a Riemannian structure on $\mathbb{R}^n $with two non homeomorphic compact hypersurfaces $M,N$ such that both satisfy the isoperimetric inequality. I precisely meanthe following:

$$\ell(M)=\ell(N)=\ell, A(M^o)=A(N^o)=A$$

and for every compact hypersurface $P$ with $\ell(P)=\ell$ we have $A(P^o)\leq A$

Here $\ell(M)=\int_M vol_M$ the natural volum form on $M$ naturally arises from the volum form on the underling manifold. $A(M^o)$ is the area of the bounded component of $M^c$ wrt the volum form arising from the metric