Posts Tagged ‘최수영’

2014 KAIST CMC Discrete Math Workshop

Sunday, November 23rd, 2014
December 10–12, 2014
자연과학동(E6-1), KAIST

Preregistration in deadline: Dec. 5 (Friday)

Program (Dec.10 Wed-Room 1409)
  • 1:30-2:00 Registration
  • 2:00-2:30 Young Soo Kwon (권영수), Yeungnam University: A variation of list coloring and its properties
  • 2:40-3:10 Mitsugu Hirasaka, Pusan National University: Small topics on association schemes
  • 3:10-3:40 Coffee Break
  • 3:40-4:10 Younjin Kim (김연진),  KAIST: On Extremal Combinatorial Problems of Noga Alon
  • 4:20-4:50 Jang Soo Kim (김장수),  Sungkyunkwan University: A new q-Selberg integral, Schur functions, and Young books
  • 5:00-6:00 Discussion
  • 6:00- Dinner
Program (Dec.11 Thurs-Room 1501 & 3435)
Program (Dec.12 Fri-Room 1501)

Suyoung Choi (최수영), The rational Betti number of small covers and its combinatorics

Tuesday, October 29th, 2013
The rational Betti number of small covers and its combinatorics
Suyoung Choi (최수영)
Department of Mathematics, Ajou University
2013/11/13 Wednesday 4PM-5PM
ROOM 1409

A small cover is a topological analogue of real toric varieties, and is an important object in toric topology. It is noted that the formula of the ℤ2-cohomology ring of small cover is well-known. However, the integral cohomology ring of small covers has not been known well.

In this talk, we discuss about the Betti numbers and its torsion of the small covers associated to some nestohedra including graph associahedra. Interestingly, the Betti numbers can be computed by purely combinatorial method (in terms of graphs and hypergraphs). To our surprise, for specific families of graphs, these numbers are deeply related to well-known combinatorial sequences such as the Catalan numbers and Euler zigzag numbers.