【115/4/21】15:20-16:10 DongSeon Hwang (Center for Complex Geometry - Institute for Basic Science (CCG-IBS), Korea)
| Geometry Seminar | |
|---|---|
|
|
|
| Time | 2026-4-21 13:30-15:00 |
| Venue | 31203, Department of Mathematics |
| Speaker | DongSeon Hwang (Center for Complex Geometry - Institute for Basic Science (CCG-IBS), Korea) |
| Title | Cascade Structures on Rational Q-homology Projective Planes |
| Abstract | A normal projective surface with quotient singularities is called a Q-homology projective plane if the topological second Betti number equals one. Several problems in differential topology, including the Montgomery--Yang problem and the rationality of the base of Sasaki--Einstein 5-manifolds, motivate the classification of Q-homology projective planes. In this talk, after briefly reviewing the classification of Q-homology projective planes, we focus on the rational case. In particular, we propose a conjecture asserting that such surfaces admit a certain birational relation, called a cascade, which implies the algebraic Montgomery--Yang problem. We conclude by showing that the conjecture holds if the anticanonical divisor is ample. |
|
|
|
