How do curved spheres intersect in 3-space?
Abstract
The following problem was proposed in 2010 by S. Lando. Let and be two unions of the same number of disjoint circles in a sphere. Do there always exist two spheres in 3-space such that their intersection is transversal and is a union of disjoint circles that is situated as in one sphere and as in the other? Union of disjoint circles is {\it situated} in one sphere as union of disjoint circles in the other sphere if there is a homeomorphism between these two spheres which maps to . We prove (by giving an explicit example) that the answer to this problem is "no". We also prove a necessary and sufficient condition on and for existing of such intersecting spheres. This result can be restated in terms of graphs. Such restatement allows for a trivial brute-force algorithm checking the condition for any given and . It is an open question if a faster algorithm exist.
Cite
@article{arxiv.1210.7361,
title = {How do curved spheres intersect in 3-space?},
author = {Sergey Avvakumov},
journal= {arXiv preprint arXiv:1210.7361},
year = {2014}
}
Comments
9 pages, 9 figures