Fake 4-ball
From HandWiki
Short description: Mathematical topological manifold
In mathematics, a fake 4-ball is a compact contractible topological 4-manifold. Michael Freedman proved that every three-dimensional homology sphere bounds a fake 4-ball. His construction involves the use of Casson handles and so does not work in the smooth category.
References
- Alexandru Scorpan, The Wild World of 4-Manifolds, American Mathematical Society, ISBN:0-8218-3749-4
 |  |
