Soap bubbles and isoperimetric regions in the product of a closed manifold with Euclidean space
arXiv:1312.6311
Abstract
For any closed Riemannian manifold we prove that large isoperimetric regions in are of the form (Euclidean ball). We prove that if has non-negative Ricci curvature then the only soap bubbles enclosing a large volume are the products (Euclidean sphere). We give an example of a surface , with Gaussian curvature negative somewhere, such that the product contains stable soap bubbles of arbitrarily large enclosed volume which do not even project surjectively onto the factor.
4 figures