• Area of Research: Topology
  4-dimensional manifolds, surfaces in 4-manifolds, knot theory,
  singularity of differential maps, singularity of complex curves
  
• List of Papers , Recent Papers
  
• curriculum vitae

Supported by JSPS KAKENHI Grant Number No. 24540070 (2012--) and No. 16K05143(2016--)

I am an organizer of

• The 12th East Asia School of Knots and Related Topics (13--16 Feb., 2017)
• Differential Topology '17 (28--31 Mar., 2017/UEC) with Prof. M. Tange (Tsukuba University) and Prof. T, Abe (OCU).

• Dehn surgery along the Mazur link and Akbulut-Yasui links   (Jan. 2016)
  The 11th East Asian School of Knots and Links (Osaka City Univ.)
  Talk slide   (pdf file, 552 KB)

  A hyperbolic 3-manifold that has torus boundaries can change to a non-hyperbolic 3-manifold by filling a boundary by a solid torus. But the number of such fillings are at most finitely many (for a fixed hyperbolic manifold), and they are called exceptional Dehn filling/surgery. The Akbulut-Yasui link is a family of generalization of the Mazur link, a symmetric two-component hyperbolic link, as diagrams of corks, ie, a contractible piece that can change the differential structures of 4-manifolds by cork twists. We study the exceptional Dehn surgeries along the Akbulut-Yasui links by using Martelli-Petronio-Roukema's results on exceptional Dehn surgeries on the minimally twisted five-chain link. Here, I thank to Y.Kabaya for his nice suggestion.

• Divide knot presentation of Berge's knots of lens space surgery   (Sept. 2010)
  Singularities, knots, and mapping class groups in memory of Bernard Perron (Dijon, FRANCE)
  Talk slide   (pdf file, 464.0KB)

  Every knot in Berge's list of lens space surgery (ie, knots yielding a lens space by Dehn surgery) is presented as a divide knot. In generic case, such a knot is presented by a billiard plane curve in "L-shaped" region, and the area of the pool is equal to the surgery coefficient. In this research, Couture- Perron's formula works very helpfully.

I was an organizer of

• Differential Topology '16 (20--22 Mar. 2016/Tsukuba) with Prof. M. Tange (Tsukuba University) and Prof. T, Abe (OCU).

I was an organizer of

• Differential Topology '15: Past, Present, and Future (25--27 Mar. 2015/Kyoto) with Prof. M. Tange (Tsukuba University) and Prof. T, Abe (T.I.T).

I was an organizer of The 9th East Asia School of Knots and Related Topics (14--17 Jan. 2013/Tokyo)

I was an organizer of

• Workshop on Casson-Freedman theory (17--20 Oct. 2009/Kyoto) with Prof. M. Furuta (Tokyo University) and Prof. T. Kato (Kyoto University).
   

• Meeting on Casson Handle (25--28 May, 2007) with Prof. Tsuyoshi Kato(Kyoto University).
   
• Low- and Infinite- dimensional geometry (11--14 Sept., 2007) with Prof. M. Furuta, H. Sasahira (Tokyo University).
  
• The Fourth East Asia School of Knots and Related Topics (21--24 Jan., 2008)
  Excurtion,   Tokyo(Shibuya/Shinjuku)

I advised my first student (undergraduate, from )
    My Faculty was "Systems-Engineering", and my main work (in education) is giving basic mathmematics lectures
    to the first grade students, but I can teach students who want to study mathematics.
Finally, my first student succeed to pass the entrance exam. of Math. faculty of a certain Univ.

From Tokyo Haneda Airport to Chofu

On the way from Tokyo (Haneda) Airport to Chofu City. As a choice, "Airport Limousine Bus"is better.

Around 18:00 and 7:00, public transportation is the most crowded by rush hour. When you go to Haneda Airport, please choose the bus enough early, or choose trains.

Chofu to Haneda Airport

Haneda Airport has three stations:
  1) Haneda Airport Terminal 1
  2) Haneda Airport Terminal 2
3) Haneda Airport International Terminal

Chofu to Haneda Airport by trains: at least two changes

[Chofu] --(Keio)->
[Shinjuku] --(JR Yamanote)->
[Shinagawa]  --(Keihin Kyuko)-> 
[Haneda] 

or

[Chofu] --(Keio)-> 
[Shinjuku] --(JR Yamanote)->
[Hamamatsu-cho] --(Monorail)-> 
[Haneda]